Add subtitle files as translatable formats.

The SubRip Text, WebVTT and SubView formats are a moderately
global format for translating and displaying subtitles in videos.
Okapi provided a nice interface via the Regex Filter for upload.
New extensions supported are srt, vtt, sbt and sub.
Merge pull request #359 from zanata/srt-support

Add subtitle files as translatable formats.
add annotation and test run listener to enable recording zanata features
add support to record TCMS test case and plan
Use feature inventory on a per test basis

Add the Feature annotation to individual tests for validation
test of concept.

Also:
- stabilise the maintaner settings functions, as they were a
bit flaky
- better checks for the version link as, in some cases, the
Translate Options menu is detected instead
Merge pull request #413 from zanata/feature-inventory

add annotation and test run listener to enable recording zanata features
Convert to assertj and clean up Account tests

- Annotate feature inventory
- Replace hamcrest with assertj
- Remove some unnecessary steps
- Add 'throws Exception' on tests
- Start using static variables for page messages