Docker integration

Lint models/user.go

Lint models/repo

Project unification, updates for contributors guide and github files

Golint fixed for models/issue_comment.go

In order to automatically build docker images I have re-enabled the
docker building parts within our drone runs on every push to master and
on every tag.

Signed-off-by: Thomas Boerger <tboerger@suse.de>

I have restructured the docker build process entirely, the binary gets
built outside of the docker build command, now we are managing all
dependencies with real Alpine packages and I have dropped features like
socat or the cron daemon.

Signed-off-by: Thomas Boerger <tboerger@suse.de>

Golint for models/org_team.go

Golint fixed for modules/auth

Fixes typos

Lint models/org.go

Golint fixed for modules/log

Lint models/repo_mirror.go

Lint models/repo_branch.go

Lint models/ssh_key.go

Lint models/access.go

Lint models/user_email.go

modules/process: add ExecDirEnv (next to ExecDir)

Add a sibling to ExecDir which is capable of specifying environment variables,
so that we can invoke `git` with GIT_INDEX_FILE, GIT_DIR, etc..

For #258

Update locales and add Swedish

Fix HTTP headers for issue attachment download