Add a folder for travis.
Put PHP extension installation into a shell script.
Merge pull request #252 from bantu/travis/reorganisation

Reorganise travis configuration

* bantu/travis/reorganisation:
  Put PHP extension installation into a shell script.
  Add a folder for travis.
Merge branch 'master' into php5

* master:
  Put PHP extension installation into a shell script.
  Add a folder for travis.