Added:
- A new action for waiting for a specific number of seconds.  Built the
info, action, and editor, as well as doing all the necessary
registering.
Altered:
- the SGM, IDEAS, and REIXS scan controllers that used the old
AMTimedWaitAction3 to use the new AMWaitAction.

Removed:
- AMTimedWaitAction3 and AMTimedWaitActionInfo3.
Fixed merge conflict with branch Issue659.