For the moment there is only uninstalling by name that works because #207

Clean take care of deleting plugins with same name and different versions
(the lower versions will be deleted)

Now in verbose mode we are printing all plugins, even those with duplicated
names and different versions

the action is named plugins

For the moment a new action for lodel_admin has been added : list-plugins
With two options : verbosity and output formatted in CSV

Test passes

Now when running distclean ALL files generated by the ./bootstrap && ./configure && make are deleted.
Maybe it's not a good idea because it's not the purpose of distclean target...

Created groups (they can be found under the "Modules" menu -_- )
Created new pages : on LeAPI EditorialModel Plugins etc

No need of -d flag to specifiy directories

- add a -L options to list availables actions

- Allow to extend easily lodel_admin.py script.
- Writtent first lodel_admin.py action : discover-plugins