Merge branch 'marmalade_iaphelper'
Updated Unity plugin readme

Added info about manifest and proxy activity
feature
Merge pull request #146 from GrimReio/unity-available-stores-option

Unity options decorator. Possibility to set only needed stores
Merge pull request #145 from GrimReio/marmalade_squash

OpenIAB: Marmalade SDK Support
Javadoc on discoverOpenStores()