Add per project directory volumes

[Olivier Sallou]

Set possibility to specify some directory volumes per project. List of dirs will be appended to available volumes when project is selected. Only admin can set directories for the project. "dir_path, dir_on_container, mode"

[Olivier Sallou]

fixed with commit 58f0f463623b9f87db74a9be15cd79804890e20c and go-docker-web: c3a7cae59cb073215e551b6e57a2f3b8dbf4ea0d