SSP-1803 Default new Plans to active

When in edit mode, the proposed active state will be the Plan's current
status. This worked in rel-2-0-patches for 2.0.1 as of
dac9036fbd2f43eb93bfb83c400db0af111a0c9d and appears to match the
current behavior in 2.1.0 at the same time.

That *new* Plans were defaulting to inactive, though, appears to
have been a regression from dac9036fbd2f43eb93bfb83c400db0af111a0c9d.