Join+a+Group

== =__Join a Group:__= Synopsis: A Faceplace User joins a desired user group. Actor/User: Faceplace User Preconditions: The User is logged in and currently viewing the group they desire to join. Sunny Day Case: Rainy Day Case #1:
 * 1) The User clicks on a join group button that is on the group's page. (See Rainy Day #1)
 * 2) The User remains on the same page, but is informed that they are now part of that group.
 * 3) The User's information is updated, the group is added to the user's lists of joined groups.
 * 1) If the User is already a member of the group, they will see a leave group button instead of the link/button to join. 