Deploying OS-specific patches PPA

Written for elementary OS by Sergey "Shnatsel" Davidoff on 2012-03-04

The recently created PPA for OS-specific patches got its first packages today!

First of all, it's elementary-os-overlay package, which forces apt to install package versions from that PPA even if there are newer versions in Ubuntu archive. Patched packages have a newer version than original ones, but when a package is updated in Ubuntu, it might build faster than our patched version, and the system will upgrade to an unpatched version of the package. Today's developments prevent that.

Second, the PPA allowed to fix a notorious bug 799694 easily; it was a rather trivial Casper patch. Recent additions to Casper turned out to be undocumented, so I've proposed a fix upstream :)

Finally, we've managed to get rid of Qt in the ISO but still get all compatibility packages to install when a Qt app is installed. Well, almost XD It's theoretically solved, but the recipe fails with out-of-memory error (Qt4 is 620Mb of source code after all!). This is being investigated in https://answers.launchpad.net/launchpad/+question/189636

If you're reading this, you're probably a developer, so, happy hacking!