give back individual control to start and cancel individual tile reconstruction

In older versions the user could set the limits of a reconstruction and individually select or cancell tiles being reconstructed. THis is very useful when you need to replace one improved tile instead of re-running a whole production. Sometimes multiple tiles are needed of the total, but that is not known until later. So we setup the whole area, and only produced tiles as they were needed. Also Sometimes we want test a specific tile FIRST in a production to make sure the area is good. Currently you cannot choose the order of the tile being produced so it is hard to test specific areas.