Changes

Only ever insert one coast

When the current stage (in case of 'coast before') or the next stage (in
case of 'coast after') occurs multiple times in the stage stats, PVG
inserts a coast before/after _each_ of them. This should not happen,
there should only ever be one coast stage.
 (commit: 1eba9de)

Fix coasts after the early shutoff stage

When a coast is inserted immediately after the "Early shutoff stage",
RCS does not get enabled and the `StartCoast` variable doesn't get set;
this means that the coast time does not tick down.

This patch makes it so both those things do get done when starting the
coast after the early shutoff stage.
 (commit: 8824457)