Updates documentation on skipping cached launch event
Updates documentation on skipping cached launch event

For supporting subscribe call from async method, the timeout code was removed.
In order to give flexibility to the user in handling initial event, some changes are made to let user skip or use the cached event.
BranchMetrics/react-native-branch,BranchMetrics/react-native-branch,BranchMetrics/react-native-branch-deep-linking,BranchMetrics/react-native-branch-deep-linking,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