Overhauled llvm/clang docs builds. Closes PR6613.

NOTE: 2nd part changeset for cfe trunk to follow.

*** PRE-PATCH ISSUES ADDRESSED

- clang api docs fail build from objdir
- clang/llvm api docs collide in install PREFIX/
- clang/llvm main docs collide in install
- clang/llvm main docs have full of hard coded destination
  assumptions and make use of absolute root in static html files;
  namely CommandGuide tools hard codes a website destination
  for cross references and some html cross references assume
  website root paths

*** IMPROVEMENTS

- bumped Doxygen from 1.4.x -> 1.6.3
- splits llvm/clang docs into 'main' and 'api' (doxygen) build trees
- provide consistent, reliable doc builds for both main+api docs
- support buid vs. install vs. website intentions
- support objdir builds
- document targets with 'make help'
- correct clean and uninstall operations
- use recursive dir delete only where absolutely necessary
- added call function fn.RMRF which safeguards against botched 'rm -rf';
  if any target (or any variable is evaluated) which attempts
  to remove any dirs which match a hard-coded 'safelist', a verbose
  error will be printed and make will error-stop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103213 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/main/CommandGuide/index.html b/docs/main/CommandGuide/index.html
new file mode 100644
index 0000000..7179675
--- /dev/null
+++ b/docs/main/CommandGuide/index.html
@@ -0,0 +1,155 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
+                      "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+<head>
+  <title>LLVM Command Guide</title>
+  <link rel="stylesheet" href="../llvm.css" type="text/css">
+</head>
+<body>
+
+<div class="doc_title">
+  LLVM Command Guide
+</div>
+
+<div class="doc_text">
+
+<p>These documents are HTML versions of the <a href="man/man1/">man pages</a>
+for all of the LLVM tools.  These pages describe how to use the LLVM commands
+and what their options are.  Note that these pages do not describe all of the
+options available for all tools.  To get a complete listing, pass the
+<tt>-help</tt> (general options) or <tt>-help-hidden</tt> (general+debugging
+options) arguments to the tool you are interested in.</p>
+
+</div>
+
+<!-- *********************************************************************** -->
+<div class="doc_section">
+  <a name="basic">Basic Commands</a>
+</div>
+<!-- *********************************************************************** -->
+
+<div class="doc_text">
+
+<ul>
+
+<li><a href="llvm-as.html"><b>llvm-as</b></a> -
+    assemble a human-readable .ll file into bytecode</li>
+
+<li><a href="llvm-dis.html"><b>llvm-dis</b></a> -
+    disassemble a bytecode file into a human-readable .ll file</li>
+
+<li><a href="opt.html"><b>opt</b></a> -
+    run a series of LLVM-to-LLVM optimizations on a bytecode file</li>
+
+<li><a href="llc.html"><b>llc</b></a> -
+    generate native machine code for a bytecode file</li>
+
+<li><a href="lli.html"><b>lli</b></a> -
+    directly run a program compiled to bytecode using a JIT compiler or
+    interpreter</li>
+
+<li><a href="llvm-link.html"><b>llvm-link</b></a> -
+    link several bytecode files into one</li>
+
+<li><a href="llvm-ar.html"><b>llvm-ar</b></a> -
+    archive bytecode files</li>
+
+<li><a href="llvm-ranlib.html"><b>llvm-ranlib</b></a> -
+    create an index for archives made with llvm-ar</li>
+
+<li><a href="llvm-nm.html"><b>llvm-nm</b></a> -
+    print out the names and types of symbols in a bytecode file</li>
+
+<li><a href="llvm-prof.html"><b>llvm-prof</b></a> -
+    format raw `<tt>llvmprof.out</tt>' data into a human-readable report</li>
+
+<li><a href="llvm-ld.html"><b>llvm-ld</b></a> -
+    general purpose linker with loadable runtime optimization support</li>
+
+<li><a href="llvm-config.html"><b>llvm-config</b></a> -
+    print out LLVM compilation options, libraries, etc. as configured</li>
+
+<li><a href="llvmc.html"><b>llvmc</b></a> -
+    a generic customizable compiler driver</li>
+
+</ul>
+
+</div>
+
+<!-- *********************************************************************** -->
+<div class="doc_section">
+  <a name="frontend">C and C++ Front-end Commands</a>
+</div>
+<!-- *********************************************************************** -->
+
+<div class="doc_text">
+<ul>
+
+<li><a href="llvmgcc.html"><b>llvm-gcc</b></a> -
+    GCC-based C front-end for LLVM
+
+<li><a href="llvmgxx.html"><b>llvm-g++</b></a> -
+    GCC-based C++ front-end for LLVM</li>
+
+</ul>
+
+</div>
+
+<!-- *********************************************************************** -->
+<div class="doc_section">
+  <a name="debug">Debugging Tools</a>
+</div>
+<!-- *********************************************************************** -->
+
+
+<div class="doc_text">
+
+<ul>
+
+<li><a href="bugpoint.html"><b>bugpoint</b></a> -
+    automatic test-case reducer</li>
+
+<li><a href="llvm-extract.html"><b>llvm-extract</b></a> -
+    extract a function from an LLVM bytecode file</li>
+
+<li><a href="llvm-bcanalyzer.html"><b>llvm-bcanalyzer</b></a> -
+    bytecode analyzer (analyzes the binary encoding itself, not the program it
+    represents)</li>
+
+</ul>
+</div>
+
+<!-- *********************************************************************** -->
+<div class="doc_section">
+  <a name="internal">Internal Tools</a>
+</div>
+<!-- *********************************************************************** -->
+
+<div class="doc_text">
+<ul>
+
+<li><a href="FileCheck.html"><b>FileCheck</b></a> -
+    Flexible file verifier used extensively by the testing harness</li>
+<li><a href="tblgen.html"><b>tblgen</b></a> -
+    target description reader and generator</li>
+<li><a href="lit.html"><b>lit</b></a> -
+    LLVM Integrated Tester, for running tests</li>
+
+</ul>
+</div>
+
+<!-- *********************************************************************** -->
+
+<hr>
+<address>
+  <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
+  src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
+  <a href="http://validator.w3.org/check/referer"><img
+  src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
+
+  <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br>
+  Last modified: $Date$
+</address>
+
+</body>
+</html>