[RNBranch.m] add rewards methods, formatting
[RNBranch.m] add rewards methods, formatting

BranchMetrics/react-native-branch,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch-deep-linking,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch-deep-linking,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch-deep-linking,BranchMetrics/react-native-branch-deep-linking