Get rid of plUruLauncher

[diafero]

The starting phase of CWE with two binaries working together is needlessly complicated, not to mention all the duplicated code. The self-patching ability and the plClientPatcher should be moved to plClient and launched before showing the login dialogue (so that nothing changes for the user). Then we can also get rid of these hard-coded .exe filenames in the sources, I see no reason why we should not be able to call the executable the way we want without even recompiling.
The internal client can get a command-line option to skip the patching, to replicate the behaviour of directly calling plClient.

[diafero]

After giving the launcher a closer look, I changed my mind on this: It's not a good idea to merge it into plClient. It should be re-written entirely, from scratch... the subject still holds valid, though ;-)

[branan]

Absolutely agree that plUruLauncher could be rewritten, but we'll always have a launcher app. I'm going to close this, and when we have a better idea how we want to handle launching we can open issues related to the fixes that need to be made.