We're getting segfaults in places where this isn't checked. Also, add
some asserts so we can catch bad tool push/pop.
Removes all uses of GetCommandStr() and makes it private.
The move tool can stack on others, so when we re-enter the previous tool
this caused another immediate action. We flag re-entry in the tool
stack to check for this and avoid unexpected tool starts
This time remove the push/pop from the picker tools as that's
responsible for the issue of trying to re-activate the move action
when its popped. Instead do the push/pop from the client code
of other actions that need it, and not at all from the move-with-
reference action.
Fixes https://gitlab.com/kicad/code/kicad/issues/5336
Mike Williams
Jeff Young
Ian McInerney
Seth Hillbrand