js-build/main.js.gz seems to be based on old version of js-build/main.js

I experienced a strange bug when developing on a local Apache setup and deploying to an Nginx environment. Cropping images always failed with this error message in the AJAX response:

```
CSRF Check failed
```

The Apache setup did not serve the gzipped version whereas the nginx setup did.

I compared the md5sums of the the gzipped version in the master branch (and the WP plugin repository for version 2.4.2) and a manually compiled and gzipped version of master. The differ and the bug described above does not occur with the manually gzipped version.

Moreover the commits leading to v2.4.2 (https://github.com/sewpafly/post-thumbnail-editor/commit/86ce4dec2ee1f40c6225ba7a5416e1a3ce55d41c) do not include a rebuilt main.js.gz if I'm not mistaken.