This is an important change.
So far, the project was labelled as licensed under the "AGPL" (improperly since no version of the AGPL was specified)
This commit changes the license to "AGPL + Commons Clause"
The [common clause](https://commonsclause.com/) is an additional restriction forbidding companies from taking WorkAdventure of the shelf, and reselling WorkAdventure.
This license does not forbid anyone from installing and using WorkAdventure, it only targets resellers (so SAAS exploitation of WorkAdventure is limited to TheCodingMachine).
This effectively makes WorkAdventure non open-source, but the source-code remains available for anyone to see and modify.
I put a connecting spinner around the user name when the user is connecting.
Also, if an error occurs, we will see a blinking red circle around the player name.
Most of the time, sending a disconnect event to one of the players is enough (the player will close the connection
which will be shut for the other player).
However! In the rare case where the WebRTC connection is not yet established, if we close the connection on one of the player,
the other player will try connecting until a timeout happens (during this time, the circle with the name is displayed for nothing).
So now, we send disconnection event to every body (not only the people in the group, but also to the person leaving the group)
If more than one tile was set in the "start" layer, the last tile would be selected.
Now, the tile is selected at random among available tiles.
Also, a message is issued if no tiles have been put on the "start" layer.
This is important because when we come back to the GameScene later, some properties of the GameScene object might be initialized with the values of the previous GameScene.
Like the position if the user previously disconnected.
Closes#146
Taking what was done in the LoginScene regarding character selection and putting it in its own scene.
Also, making character selection possible via the keyboard.
Remvoing messages that were no more used in the new messaging system (the code used to handle the message that sent the position of all users on the front side)
The URL signature becomes:
https://workadventu.re/_/[instance]/[path_to_map.json]
This allows us to create many instances of the same map (and therefore to create several different worlds for different people)
An exit on a map can target another "instance" by passing the "exitInstance" property.
