Added formMergeOrRewrite to project code, it wouldn't compile at home,
don't know why. But whatever.
Trying to implement hashed commands to allow convergence.

Bad thing: hash computes slowly, it should work in other thread in fact
New button 'load data points', whole new functionality,
now ve can compare data points with graph in image format, much faster then
digitizing image to text format.

after introducing events etc bug appeared that coord_system tries to draw
on nil image. Now we check if image is assigned.
LoadPointsCommand added, works fine. ClearPoints is simple modification of it.
Only one drawback: after undo initial data changes so it can't determine
if there is difference with another LoadPoint command.
TLoadPointsCommand: override EqualsByAnyOtherName to check if we load exactly the same
data as it was in undone command.
AddPointsCommand is not hashed command any more (too slooooow)
Stable version 0.4!!! (it seems all right at least)

Tools are now actions (they are added by package)
commands: initialization in constructor simplified a little (all boolean are false by default)
when axis all set, add point tool is automatically selected
TCropTool: after cropping cursot reverts to cross as intended.