Fix some portability and build problems (#89)

Remove use of deprecated std::iterator.
Fix colordiff use in clang_format script (from jacob.bramley@arm.com).
Remove debugger tests from non-simulator builds.
Update code coverage record.
diff --git a/tools/clang_format.py b/tools/clang_format.py
index 2a08180..a9c53c9 100755
--- a/tools/clang_format.py
+++ b/tools/clang_format.py
@@ -128,10 +128,11 @@
             stdin = p_diff.stdout,
             stdout = subprocess.PIPE, stderr = subprocess.STDOUT)
     out, unused = p_colordiff.communicate()
+    rc += p_colordiff.returncode
   else:
     out, unused = p_diff.communicate()
+    rc += p_diff.returncode
 
-  rc += p_diff.returncode
 
   if in_place:
       cmd_format = [clang_format, '-i', filename]