unified XML indentation
added XSD to PHPUnit configuration
no need to backup globals for tests
loop optimizations
removed some useless code from tests
finer grained Composer requirements
use Coveralls for test coverage tracking
use whitelist instead of blacklist for coverage analysis to properly exclude cache files generated by tests
let Travis build fail on Coveralls error
added more tests for better code coverage
added badges from Travis and Coveralls
Added PHP 5.6 and HHVM to travis.yml

I fixed the build matrix. We want to reduce the number of redundant runs
Merge pull request #139 from Nyholm/patch-1

Added PHP 5.6 and HHVM to travis.yml
removed trailing whitespace
moved library-related code into the dedicated FormFlow folder
use a compiler pass to register translation files in their new location