Merge pull request #14 from baasbox/master

pull request from repository baasbox
Merge pull request #16 from lupatellimatteo/master

align customDataPush
add sound feature for ios push notifications
add additional data for push notifications
add error if missing key title in JSONObject in customData
fixed error if customData is only a value
Merge pull request #17 from lupatellimatteo/customDataPush

merge into pushProfile branch customDataPush