Overall improvement of the views

Added

• Support of IEEE files [feature demo]
• Creation of a main apps menu [feature demo]
• Enable Pan/Zoom in a substation window [feature demo]
• Center the map on a substation on user clicks [feature demo]
• All/none actions for the voltage levels on the map [feature demo]

Changed

• New fancy study-add button [feature demo]
• undefined is no more displayed in the substation list when country info is unavailable [feature demo]

Fixed

• Fix authentication when reloading [feature demo]