Merge branch 'release/1.4.0' into develop
Fixes failing test for PHP 5.3
Fixes development mode CSS path bug in OptionsManifest.

* Adds extra alias in development to allow frontend build scripts to
  build app.js or wp-foo.js.
Bumps version to 1.5.0.
Updates Changelog for 1.5.0
Merges branch 'release/1.5.0'