delete superfluous environment variables
explicitly install sudo

```deploy.sh``` in the docker container requires ```sudo```; this should resolve #127.
Merge pull request #124 from fundon/delete-superfluous-variable

delete superfluous environment variables
Merge pull request #129 from shabbychef/patch-1

explicitly install sudo
Merge branch 'master' of github.com:gogits/gogs into dev
bug fixed
Merge branch 'dev' of github.com:gogits/gogs into dev
Fix #102