Link to explanation for compilation issues with custom Cocoapods configurations.
Support constant values in tweaks.

Two fixes here:
 - Cast points to (void *) before storing in struct to avoid warning.
 - Update _Generic to support const types in addition to regular ones.
Added in full export support.

 - offloaded the dictionary representation to FBTweakStore
 - adjusted toolbar to not have a hardcoded height
 - Cleaned up tableview insets, and cleaned up mail handling
 - Fixed plist exporting
Merge branch 'master' of https://github.com/facebook/Tweaks

# By Grant Paul (2) and Kevin Harwood (1)
# Via Grant Paul
* 'master' of https://github.com/facebook/Tweaks:
  Added in full export support.
  Support constant values in tweaks.
  Link to explanation for compilation issues with custom Cocoapods configurations.

Conflicts:
	FBTweak/FBTweak.m
	FBTweak/FBTweakCategory.m
	FBTweak/FBTweakCollection.m