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/IntervalPartition.cpp b/llvm/lib/Analysis/IntervalPartition.cpp
index 4bff950..8616cb7 100644
--- a/llvm/lib/Analysis/IntervalPartition.cpp
+++ b/llvm/lib/Analysis/IntervalPartition.cpp
@@ -6,7 +6,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/IntervalIterator.h"
-#include "llvm/Support/STLExtras.h"
+#include "Support/STLExtras.h"
 
 using namespace cfg;