use the generic TRAVIS environment var to check for travis (see http://docs.travis-ci.com/user/ci-environment/)
switch to C travis project instead of PHP
add initial install
Merge branch 'pull-request/932' into PHP-5.5

* pull-request/932:
  add initial install
  switch to C travis project instead of PHP
  use the generic TRAVIS environment var to check for travis (see http://docs.travis-ci.com/user/ci-environment/)
Merge branch 'PHP-5.5' into PHP-5.6

* PHP-5.5:
  add initial install
  switch to C travis project instead of PHP
  use the generic TRAVIS environment var to check for travis (see http://docs.travis-ci.com/user/ci-environment/)
Merge branch 'PHP-5.6'

* PHP-5.6:
  add initial install
  switch to C travis project instead of PHP
  use the generic TRAVIS environment var to check for travis (see http://docs.travis-ci.com/user/ci-environment/)
Zend Engine 3
Removed ZEND_ENGINE_2 checks (and ZE1 code, it's been a decade!)
Note macro removal in UPGRADING.INTERNALS