Add aggressive line shortening

This helps when shortening multiline dictionaries. To enable this use
the "--aggressive" option.
Merge branch 'shorten'
Remove obsolete tests

These are no longer picked up with the development version of pep8.
Add missing r prefix
Use reversed() to avoid side effect

Also, correct the order of arguments in self.assertEqual().
Correct order of arguments in self.assertEqual()
Replace explicit close() with context manager
Mention line shortening with "--aggressive"
Add another line shortening strategy

If other strategies fail, try putting newlines after each comma token.
Remove unused variables
Remove completed item
enable input via stdin
add emacs list wrapper
don't allow filename to be specified with --stdin
use '-' for stdin instead of --stdin flag
Revert "add emacs list wrapper"

This reverts commit 8792df48806eb3c9fb9d901529e4e967520e09c2.
Format
Make Travis run pep8
Thanks
Make this work on Python 3