Dev ol3build customexports

This is a temporary hack to allow the addition of custom exports for RE3.

You need to specify the exports in the `scripts/ga-ol3.exports` file and run `make updateol` to update the ol3 build (don't forget to commit the updated ol3 build).

It adds the new regex dependency.

It changes the url to use the https protocol to get the ol3 sources (this allows any user to clone the repository without having ssh access configured).