docs: rework stuff

The existing docs were far from how we wanted it to be. There was so much to do
and it is not feasible to do that cleanup it in clean patches.

Instead, I took a sweep through the docs and changed what I thought could
benefit from a change: structure, examples, advices, language, markup, content,
etc.

Implemented basic locking functionality.

- Reimplemented how githooks behave
- emaulate pre-receive hook
- install missing git hooks if they aren't already in repo