Add test for parsing different file types

- Add tests for bzip, gzip and normal files to parser tests.
Add ability to process bzip2'd logs

Python's bz2 module is supported since version 2.3,
so all supported RHEL versions (5 and up) are fine with this.

Signed-off-by: Adrian Coveney <adrian.coveney@stfc.ac.uk>
Tidy spacing

- Convert tabs to spaces.
- Add extra space before in-line comment.
Merge pull request #55 from apel/add_bzip_support

Add bzip support