Update build script for XCode >= 4.4. Fix Mountain Lion compatibilities. Other Fixes

Other fixes include:
- Disable x264 on cross-compilations (libx264 doesn't support universal builds)
- Update Qt URL for new web site (doesn't include Qt 4.7, only 4.6.x and 4.8.x)
(cherry picked from commit 91a9a3c3b637a018359b94c5ba12b25f773089d2)
Add support for Qt 4.8.3
(cherry picked from commit f57b30d0c80c2f5726b2d013a5ba56546a886a0a)
Changes required to compile 4.8.3 on Mountain Lion
(cherry picked from commit d5133545c1814f01e74fe9079ba83d3cd21140f4)
Correct download path for Qt - Nokia -> Digia, now a new site for opensource.
(cherry picked from commit 3b8e44bed037bb84aa94f2f4dd72bf4ae198cd2c)
Tidy up plugin processing for GUI apps. (remove double if, and some tabs)
(cherry picked from commit 998fa768e28509dbbf0c3841c1d6a72755cf487e)
Newer libcdio, to support Mac OS 10.6, 10.7 & 10.8. Closes #10569
(cherry picked from commit e44fbab1238c40ed88034f626ef2445cb0003596)
Add support for latest Qt 4.8.4 and clang (xcode 4.6)

-Qt patches should now work for future 4.8.x and 4.7.x version; make patches universal per major series
-Do not build Qt doc and designer
(cherry picked from commit eedf9e6785ca6054076d1e9dd98a9527a0c9e3ca)
Fix execute bit again that xcode's git screws up
(cherry picked from commit 592e2b052b9e40f9d6247cdbd1fe5b4912d7947a)
Add mythlogserver to application bundles (MythFrontend and MythBackend)
(cherry picked from commit 71736db943781b0fbf955d4e4ef1c38d5429ba7d)