Add charity event Id generator.

[Mart1nux]

Right now the Id is simply imputed by the user when a new charity event is generated. This is a temporary solution with a high probability to have multiple charity events with identical Id's. As of right now it is believed that making GUID generator for the ID's would be the best course of action.

[ArentasMeinorius]

Entity framework will handle this for us. If noone objects I will close the item tomorrow