Merge pull request #3 from sophilabs/fix-issue-2-empty-repo

Fix issue #2, change command to get branch name.

lib/index.js

@@ -19,7 +19,7 @@ gilpUtil.getGitDirectory = function () {
 };
 
 gilpUtil.getBranchName = function () {
-  return execSync('git rev-parse --abbrev-ref HEAD').toString().trim();
+  return execSync('git symbolic-ref --short HEAD').toString().trim();
 };
 
 gilpUtil.getCommitMessage = function () {