Create a new #include "Support/..." directory structure to move things
from "llvm/Support/..." that are not llvm dependant.

Move files and fix #includes

llvm-svn: 1400
diff --git a/llvm/tools/gccas/gccas.cpp b/llvm/tools/gccas/gccas.cpp
index e19508f..c5ab2df 100644
--- a/llvm/tools/gccas/gccas.cpp
+++ b/llvm/tools/gccas/gccas.cpp
@@ -15,7 +15,7 @@
 #include "llvm/Optimizations/DCE.h"
 #include "llvm/Transforms/ConstantMerge.h"
 #include "llvm/Bytecode/Writer.h"
-#include "llvm/Support/CommandLine.h"
+#include "Support/CommandLine.h"
 #include <memory>
 #include <fstream>
 #include <string>