line[0] == "#" crashes when I open the Exercise Manager

[Quentin THEURET @Amaris]

When I try to open 'Exercise Manager' without exercises, an error occured to the terminal

Repository tab :

Traceback (most recent call last):
  File "/home/quentin/Developpement/perroquet/perroquetlib/gui/gui_exercise_manager.py", line 80, in update_exercise_list_thread
    self._update_repository_tree_view()
  File "/home/quentin/Developpement/perroquet/perroquetlib/gui/gui_exercise_manager.py", line 220, in _update_repository_tree_view
    personnalRepoList = self.repositoryManager.get_personal_exercise_repository_list()
  File "/home/quentin/Developpement/perroquet/perroquetlib/repository/exercise_repository_manager.py", line 192, in get_personal_exercise_repository_list
    if line[0] == "#":
IndexError: string index out of range

Exercise tab :

Traceback (most recent call last):
  File "/home/quentin/Developpement/perroquet/perroquetlib/gui/gui_exercise_manager.py", line 83, in update_exercise_list_thread
    self.repositoryList = self.repositoryManager.get_exercise_repository_list()
  File "/home/quentin/Developpement/perroquet/perroquetlib/repository/exercise_repository_manager.py", line 86, in get_exercise_repository_list
    repositoryList += self._get_distant_exercise_repository_list()
  File "/home/quentin/Developpement/perroquet/perroquetlib/repository/exercise_repository_manager.py", line 132, in _get_distant_exercise_repository_list
    if line[0] == "#":
IndexError: string index out of range