* Replace ActionsMapSignals to MoulinetteSignals and make it available through 'msignal' global variable
* Update interfaces to support signals changes
* Add a new signal 'display' and implement it in the cli
* Move actions map parsers classes into their respective interface modules
* Introduce an Interface base class for a futur usage
* Each interfaces must now implement ActionsMapParser and Interface classes
* Standardize interface instantiation
* Move authenticators classes into distinct modules
* Standardize MoulinetteError which is now a child class of IOError
* Add methods from helpers.py to LDAP authenticator class
* Review authenticator and action configuration storage
* Small changes in error printing on MoulinetteError raising
* Update the API to support authenticators and session token
* Add a function to clean sessions
* Make the API fit in better with actions map
* Minor changes on test namespace
* Modify global configuration in the actions map
* Implement getter/setter for global and action configuration
* Implement quickly authenticators classes and add a todo LDAP authenticator
* Implement an actions map signals system and add some signals
* Add a Moulinette Interface for the cli and make it support signals
* Add a test namespace which implements configuration and authentication
* Move general_arguments to _global.arguments in the actions map
* Introduce global configuration in the actions map (need implementation!)
* Standardize arguments addition during the parser construction
* Fix action name with '-'
