Enhance tox output and fix spec formatting

Include file name for specs with missing subtitles. Include file name for specs
with docutils errors. Removed empty file.

Formatting errors fixed in specs:
* Line length past 79 characters.
* Consistent capitalization of subtitles (first word only, which was the
  majority of the existing ones).
* Missing subtitle.
* Unexpected indentation.
* Title underline length too short.

Change-Id: Ie319c80142bdc706cb849e8870d96f44b2045dcd