Silence tvOS warning

Bump deployment target

Update version in the readme

Version bump.

Version bump to 0.9.1.

Version bump.

Version bump to 0.8.

Version bump to 0.7.

Removed screenshot entries from the podspec.

Major code rewrite / cleanup. closes #56 #60

- MBProgressHUD now requires LLVM 3+

- instance variables moved to the class implementation or removed (using synthesized instance vars)
- using KVO instead of custom accessors
- completely rewritten layout and UI buildup code
- more concise arc conditionals
- added MBProgressHUDModeText (+ example)
- various documentation fixes
- migrated to @autoreleasepool
- general source code cleanup and restructuring
- removed deprecated delegate callback
- version bump to 5.0