tools/verifygitlog.py: Show invalid commit subjects in quotes.

If a commit subject line has any trailing whitespace it won't match the
repository validation rules, and the line will show up as part of the
relevant error message.  However, since there's no quotation marks
around the offending text, the trailing whitespace may go unnoticed, and
given that the commit message is then discarded when the commit
operation is retried this can get fairly annoying.

This commit simply modifies the error output for invalid subject lines
to add quotation marks around the offending text, so trailing whitespace
is much easier to see.

Signed-off-by: Alessandro Gatti <[email protected]>

Author: agatti

tools/verifygitlog.py

@@ -47,7 +47,7 @@ def git_log(pretty_format, *args):
 
 
 def diagnose_subject_line(subject_line, subject_line_format, err):
-    err.error("Subject line: " + subject_line)
+    err.error('Subject line: "' + subject_line + '"')
     if not subject_line.endswith("."):
         err.error('* must end with "."')
     if not re.match(r"^[^!]+: ", subject_line):