Update yunohost_app.py

yunohost_remove is not a file!
Update yunohost_app.py

use shutil
Merge pull request #27 from jeromelebleu/dev

Update bash completion
Update firewall.yml
I am Batman
Merge branch 'dev' of github.com:YunoHost/moulinette into dev
Metronome cert bugfix
Metronome cert bugfix
Merge pull request #26 from titoko/dev

Update yunohost_app.py
dspam switch fix
Merge branch 'dev' of github.com:YunoHost/moulinette into dev