Change to explicitly specifying architectures as armv7, armv7s and arm64.

This adds armv7s over the Xcode 6 standard architectures.
The library can now be linked with with apps that include an armv7s slice.
Fix NSShadow customization option implementation
Merge pull request #316 from douglashill/architectures

Fix library failing to link when compiling app for armv7s.
Sync UVStyleSheet with [UINavigationBar apparence]

Before:
https://www.dropbox.com/s/1bfj7y2o2u7c12w/Before.png?dl=0
After:
https://www.dropbox.com/s/d6xeo0tv3ngt72g/After.png?dl=0
Call super implementation when overriding methods
Merge pull request #320 from sodastsai/master

Call super implementation when overriding methods
Merge pull request #319 from zhxnlai/master

Sync UVStyleSheet with [UINavigationBar apparence]
Merge remote-tracking branch 'upstream/master'