When enabled, repeating locks are not automatically cleared when
a new point is added. They are handy when the same constraint
must be repeated for multiple points (eg adding vertices
which are always 50 meters apart)
(fix#12605)
constraint is locked
The previous behaviour was that the constraint had to be "relocked"
if the user manually altered the constraint value in the text
widgets. Now users can edit the constraint value after already
locking the constraint.
