Documentation fix

Fix inaccurate headerdoc
make multiple choice cell backgrounds clear on ipads
Objective C modernization refactor
Missed a spot
Merge pull request #85 from Threadflip/master

Documentation fix
Add bridge casts for casting from Mixpanel* to void* and back
Remove radio change observer on dealloc, also get ready for ARC by removing retain cycle (change __block to __weak when we turn on ARC)
Better idea, make it a regular notification observer with a selector
use iVar instead of self.
Fix more ARC issues, retain serialQueue and telephonyInfo
Running ARC conversion wizard
Make strong copies of weakly held references before using them. Avoids some nasty potential issues
Add preprocessor macro to allow disabling IFA
Be more clear where to define the MIXPANEL_NO_IFA macro
strip out ios 7 symbol when building with sdk 6
Add current podspec
Merge branch 'master' into arc
style
Add syntax fixer script to enforce conventions. Ran it on project
Copy properties before heading off into the background in case the passed-in dictionary is mutable.