Publish to coveralls.io from travis.
Coverage for commands that are usually lazyRequired.

Gives a more accurate coverage figure (went down 10%).
Forward more logging events for testing purposes.

e.g. can now see `'log'` events on the logger returned from
`bower.commands.init()`.
Basic test for init command.
Add more simple command tests.
Add coverage coverall badge
Move all test temp files to test/tmp
Refactor integration tests to separate files