Fixing sockets and cleaning

- The socket now connects either to localhost:9091 or to graasp.eu and wait that the previous actions are loaded before listening.
- When connecting to the standalone view, the ILS emit the access action with target and object not referring to the same space. It is then more reliable to get the phase ID from the target instead of the object
- Improvement of the verification to avoid a user to appear several times in the online users gadget
- The first letter of the usernames are better vertically centered in the circles (when no gravatar)
- Code cleaning

Closes #222 #223