* add isEpochSwitch function and refactor utils
* fix broken first v2 epoch switch block
* use adaptor epoch switch function to determine v1 v2 epoch swtich block
* add test for the GetMasternodesByNumber and GetCurrentEpochSwitchBlock function
* add v2 test for isAuthroisedAddress
* Use GetCurrentEpochSwitchBlock in findNearestSignedBlock api