fetch git data from command line git
- added exec-sync package to execute git commands
- if a proper git hash is not passed, falls back to default values
tests for fetchGitData
use blanket instead of jscoverage
collapsed logical block
added full test coverage on fetchGitData
use getOptions method to fetch commit data
Merge pull request #16 from gabehayes/master

better circleci support, use git executable to populate options