Added notify changes



hi Omegaice,

here 2 new ideas
1. store only when changes (save not on all clicks a new config)
2. notify changes ( show the view range as notify on changes + config option)

ps: only delete and re fork have help he show always all patches before.. 

test version:
http://wot.medi.li/download/XVMTankRange-v1.7_medi.zip