- Add note to avoid problems with shared volumes permissions
- Restructure the doc to help comprehension
- Make command examples consistent
- Improve wording in some places
- Advanced usage: remove "avoid if possible". It made little sense.
- docker (project) --> Docker
- dokku (project) --> Dokku
- dokku (command) --> `dokku`
- add `shell` to code blocks
My changes may not be quite correct, but as far as I can tell, DOCKER_OPTIONS now requires specifying a phase explicitly.
Also updated references to `--link` since `-link` has been deprecated in Docker.