Added some tweaks in map editing and town palette

- Added shortcut to Town Palette (Ctrl + T)
- Changed terminal shortcut from Ctrl + T to Ctrl + ~. In many games and apps ~ is mainly used for toggling console/terminal
- Added icon to Town Palette
- Now you can use middle mouse button + ctrl to reset map zoom
- Now Ctrl key is used to delete items from map (I think that on Shift key we should add functionality from Shift in RME)