Factored out Linux proc file reading into separate class.

Both NativeProcessLinux (in llgs branch) and Linux Host.cpp had similar code to handle /proc 
file reading.  I factored that out into a new Linux-specific ProcFileReader class and added a method
that the llgs branch will use for line-by-line parsing.

This change also adds numerous Linux-specific files to Xcode that were missing from the Xcode
project files.

Related to https://github.com/tfiala/lldb/issues/27

llvm-svn: 212015
diff --git a/lldb/source/Plugins/Process/Linux/ProcFileReader.h b/lldb/source/Plugins/Process/Linux/ProcFileReader.h
new file mode 100644
index 0000000..dfd77d3
--- /dev/null
+++ b/lldb/source/Plugins/Process/Linux/ProcFileReader.h
@@ -0,0 +1,34 @@
+//===-- ProcFileReader.h ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_ProcFileReader_h_
+#define liblldb_ProcFileReader_h_
+
+#include <functional>
+
+#include "lldb/lldb-forward.h"
+#include "lldb/lldb-types.h"
+
+namespace lldb_private
+{
+    class ProcFileReader
+    {
+    public:
+
+        static lldb::DataBufferSP
+        ReadIntoDataBuffer (lldb::pid_t pid, const char *name);
+
+        /// Parse the /proc/{@a pid}/{@a name} file line by line, passing each line to line_parser, until
+        /// either end of file or until line_parser returns false.
+        static lldb_private::Error
+        ProcessLineByLine (lldb::pid_t pid, const char *name, std::function<bool (const std::string &line)> line_parser);
+    };
+}
+
+#endif // #ifndef liblldb_ProcFileReader_h_