Merge branch 'develop'

* develop:
  Refactored nginx fastcgi server definition into an upstream block.
  Don't expose server versions.
  PHP redis module version: 2.2.2.
  Added link to PHP Info in README.
  PHP version: 5.4.8.
Merge branch 'develop'

* develop:
  Show pruning message only if there are cache entries to be pruned.
  DRY curl calls to a bash function in `bin/compile`.
  Added a routine in `bin/compile` to clean unused cached bundles (older than 30 days). Added Tests for cache pruning.
  Nginx version: 1.2.5.
  Minor README file typo fixes.
Merge branch 'master' into develop