Make travis install from source, fixes 403 responses
Test against PHP 5.5 on travis
merged branch igorw/travis (PR #576)

This PR was merged into the master branch.

Commits
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e58fa91 Test against PHP 5.5 on travis
d3f9659 Make travis install from source, fixes 403 responses

Discussion
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Travis: Fix 403 errors, test against PHP 5.5