Update README.md
Synchronization fix + NSError in callback
changed get to post for credithistory
Added referree to credit history
Updated version to 0.3.0
resolved conflict in readme
Merge branch 'nserror'

Added NSError to callbacks.
Update README.md
Remove unused project file
Merge pull request #21 from iheartradio/remove_unused_projectfile

Remove unused project file
Synchronizing queue operations
Updated version to 0.3.1
Referral Code
add framework
Split metadata to bucket and amount
Added expiration to API
Added more overloaded Referral Code API's
Fix code errors.
Merge pull request #26 from Thinkscape/patch-1

Fix code errors.
Update README.md