Work-based commands & new user docs

Release log:

Update links for tool badges

Update installation for the Bees Hive organization

Actualize "Usage" section

Disable pushes to master branch [#119,]

Allow --force for push commands [#122]

Update documentation [#113]

Add test for 'git elegant save' command [#113]

Add "save" command [#113]

Renamed "clone" to "acquire-repository" [#129]

Rework elegant configure` command [#130]

Use MIT license for the project

Make tool installation more user-friendly

Use "beeshive" Docker organization to host CI images

Migrate documentation to ReadTheDocs format

Add ReadTheDocs configuration

Polish documentation [#140]

Check documentation in the scope of quality pipeline [#140]

Add `start-work` command [#115]

Propagate user arguments to libexec scripts

Add `accept-work` command [#137]

Introduce `save-work` command

Use `https://elegant-git.bees-hive.org` as a relevant site URL

Add `deliver-work` command

Remove `push-after-rebase` command

Remove `push` command

Remove `rebase` command

Rename `acquire-repository` command to `clone-repository`

Remove `check` command

Actualize list of available commands

Rename `init` command to `init-repository`

Remove `add` command

Actualize BASH completion function

Introduce `acquire-repository` command

Add more mandatory configurations to `acquire-repository` command

Add documentation builds badge

Polish user documentation

Describe exit codes [#73]

Reapply commits on top of `origin/master` when `accept-work`