refactor and add tests to tailing
fix regression when going below the log zone

Since a431b68c2858a2d96f35accfe577497344de98a2, when going below the max
of the log files, the position button would remain in fixed position.
This fixes it.
Polish build matrix table header

Instead of uniformly camelizing the headers, use a map of headers
each build matrix key should display in the table
Fix typo [skip ci]
Remove 'commiter' key for translations

This key is not in use anywhere else.
Merge pull request #234 from travis-ci/ha-feature-gh234-pretty_build_key_headers

Build Matrix keys should be more flexible than just being camelized
Get config headers only from jobs when preparing jobs table

After changes in travis-core, irrelevant headers are removed when matrix
is expanded. For example python version is removed from a ruby build.
Build's config is not altered, so in order to get only effective keys,
we need to iterate over jobs.
Merge pull request #233 from dmathieu/tailing

Refactor tailing and test it
Remove `mailto:` URLs

Addresses https://github.com/travis-ci/travis-ci/issues/1807
Remove Bundler patch

The patch does not seem necessary any longer.
Remove urlAuthor and urlCommitter fields

No longer in views, so no need to keep these.
Merge pull request #238 from travis-ci/ha-bug-gemfile_fix

Remove Bundler patch
Merge pull request #237 from travis-ci/ha-bug-gh_core_1807

Remove `mailto:` URLs

Closes travis-ci/travis-ci#1807.
Fix typo in Code Climate popup.