Merge pull request #3 from arvenil/update-travis

Add redis-server to travis services
Infinite loop in mutex dtor when backend is unavailable - unit test
Infinite loop in mutex dtor when backend is unavailable - fix
test/predis mock: makes available property non-static
Introduce UnrecoverableMutexException, warn about depending on __destructor() for releasing locks.
Don't use privates
Simplify lock provider
Large cleanup + reintroduce Lock __destructor() test
For redis and memcache(d)
Merge pull request #5 from arvenil/pr/4

Infinite loop in mutex dtor when backend is unavailable
Add php 5.6
Scrutinizer
Badges
Merge pull request #6 from arvenil/scrutinizer

Scrutinizer
Add Code Climate