Remove files required for phar creation. Update changelog app.

This isn't ready to merge yet, but I want to put it out there. I've updated the `build/changelog.php` app to use the Framework instead of the Platform classes. Pretty simple, I know. There is, however, one problem with it, and that is that you hit the API rate limit fairly quickly, considering we have more than 60 issues, and the limit is only 60/hr. It seems we should probably add some authentication to it. Maybe @mbabker could help with that?