feature #260 Remove HHVM support (fabpot)

This PR was merged into the 3.x-dev branch.

Discussion
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Remove HHVM support

Commits
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ab355a3 removed HHVM support

Author: fabpot

.travis.yml

@@ -30,7 +30,6 @@ matrix:
     - php: 7.0
     - php: 7.1
     - php: 7.2
-    - php: hhvm
   allow_failures:
     - env: DEPENDENCIES=dev