test_all_files_already_beautiful contains wisdom beautify_changed_files_in_branch needs

[smlewis]

https://github.com/RosettaCommons/tools/blob/master/python_cc_reader/test_all_files_already_beautiful.py#L36

print "One of the most likely reasons your file doesn't compile is that you have used a macro (e.g. TS_ASSERT) but have not followed it with a semicolon"

This warning is absolutely brilliant, and it is a shame that the user can only see it after the TEST SERVER fails to beautify. If they run beautify_changed_files_in_branch locally, it just tells them it can't do it because of mismatched {} without the helpful error message. Perhaps the message can migrate.

(I can do the idiot's version of "just always print the message" but I bet it is a 2 minute job for @aleaverfay to do the slicker "only print it if it failed on a cxxtest file").