added PHP 5.6 and HHVM to the Travis file
minor #923 added PHP 5.6 and HHVM to the Travis file (fabpot)

This PR was merged into the 1.2.x-dev branch.

Discussion
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added PHP 5.6 and HHVM to the Travis file

Commits
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ecf3acf added PHP 5.6 and HHVM to the Travis file