BaseTools/Ecc/EOT: Add Python 3 support on ECC and EOT tools.

1. Add Python 3 support on ECC and EOT tools
2. Add C grammar file of ANTLR4 and fix some bugs

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hess Chen <hesheng.chen@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

BaseTools/Source/Python/Ecc/MetaDataParser.py

@@ -113,7 +113,7 @@ def ParseHeaderCommentSection(CommentList, FileName = None):
     #
     Last = 0
     HeaderCommentStage = HEADER_COMMENT_NOT_STARTED
-    for Index in xrange(len(CommentList)-1, 0, -1):
+    for Index in range(len(CommentList) - 1, 0, -1):
         Line = CommentList[Index][0]
         if _IsCopyrightLine(Line):
             Last = Index