Ensure we don't get tabs in .xml, .zcml files.
Use rst-mode for .rst files.

Set fill-column to 79 in line with sphinx/rst conventions.
Remove use of pycheckers.py

We no longer need to use pycheckers.py, as pep8 and flake8 do the same job.
Merge pull request #10 from netsight/fix-nxml-mode-tabs

Ensure we don't get tabs in .xml, .zcml files.
Merge pull request #11 from netsight/use-builtin-pep8-and-flake8

Remove use of pycheckers.py
Merge pull request #12 from netsight/rst-mode-tweaks

Use rst-mode for .rst files.