Cleanup & optimise perfs

Closes #388 (closed), #292 (closed)

• (Perf) Changed endpoint target for project on left-menu
• (Perf) Changed behavior of Circle and Project admin
• (Fix) No more multiple join or leave buttons on admin circle, project and circle and project infos
• (Fix) Every sib-forms, sib-display and sib-delete must be properly reactive
• (New) publicDirectory parameter on config.json to allow end user to enable Profile Directory
• (New) libLocal parameter on config.json to use local /lib/ folder for dependencies.
• (New) Redirect user to login page on not logged in
• (New) Hide few UI on not logged in
• (Change) src/views folder hierarchy, ordered admin, circles, project

Todo:

• (Fix) CSS on left menu for Project @gaelleM (Please change main.scss#474 too. :))