add spec for reopen issue

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
feature: reopen issues

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
implement reopen issue for github repos

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
implement reopen issue for bitbucket repos

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
implement reopen issue for gitlab repos

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
provide an ok status on reopen issues

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
Merge pull request #35 from gittalk/reopen-issue

Reopen issue