Using of the board editor
=========================
- left mouse button can be used to drag board around
- middle and right mouse buttons can be used to drag the board bigger or smaller
 - dragging to right or down adds rows/columns and dragging to left or up
   removes them
- keyboard buttons 1-5 can be used to set the type of the block where the mouse is
 - 1: empty
 - 2: hole
 - 3: square hole
 - 4: end:
 - 5: start
- keyboard buttons 'w', 'a', 's' and 'd' can be used to toggle walls on any side of the selected square
  - 'q' and 'e' -buttons toggle diagonal walls
- ctrl-s saves the map.
- ctrl-q quits
- t opens time setting dialog
- mouse scroll moves the camera nearer or further from the board
