GitLab API list needed endpoints

[CGuichard]

As of now, we have a route "/api/proxy" that proxify requests to the GitLab REST API. Now that the development has stabilized we should create specific endpoints for each task, and not give a request proxy that may give too much access.

List of API we may need to implement:

• POST /projects/:id/star
• POST /projects/:id/unstar
• GET /projects/:id/starrers
• GET /projects/:id/issues
• POST /projects/:id/issues
• GET /projects/:id/issues/:issueID
• GET /projects/:id/issues/:issueID/notes
• POST /projects/:id/issues/:issueID/notes
• PUT /projects/:id/issues/:issueID/notes
• DELETE /projects/:id/issues/:issueID/notes/:commentID
• GET /projects/:id/issues/:issueID/notes/:cmmentID/award_emoji
• POST /projects/:id/issues/:issueID/notes/:cmmentID/award_emoji
• GET /markdown
• GET /user
• GET /users
• GET /users/:id
• GET /avatar
• GET /topics