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/lib/Analysis/LoopDepth.cpp b/llvm/lib/Analysis/LoopDepth.cpp
index 7518606..ed96bd4 100644
--- a/llvm/lib/Analysis/LoopDepth.cpp
+++ b/llvm/lib/Analysis/LoopDepth.cpp
@@ -7,7 +7,7 @@
 
 #include "llvm/Analysis/LoopDepth.h"
 #include "llvm/Analysis/IntervalPartition.h"
-#include "llvm/Support/STLExtras.h"
+#include "Support/STLExtras.h"
 #include <algorithm>
 
 inline void LoopDepthCalculator::AddBB(const BasicBlock *BB) {