[Support] Add color cl category.

This commit adds a color category so tools can document this option and
enables it for dwarfdump and dsymuttil.

rdar://problem/40498996

llvm-svn: 333176
diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
index 273c535..300a00b 100644
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -28,6 +28,7 @@
 #include "llvm/Support/Regex.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Support/WithColor.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
@@ -513,7 +514,7 @@
   llvm::InitializeAllTargetInfos();
   llvm::InitializeAllTargetMCs();
 
-  HideUnrelatedOptions({&DwarfDumpCategory, &SectionCategory});
+  HideUnrelatedOptions({&DwarfDumpCategory, &SectionCategory, &ColorCategory});
   cl::ParseCommandLineOptions(
       argc, argv,
       "pretty-print DWARF debug information in object files"