ToDos

Use svg-Sprite for all symbols and <use> them in grid and buttons
Provide more symbols, such as sword, crossbow, axe, ...
Allow textual symbols (name, a few words) to be placed on the grid
Save last edited grid in localStorage in case user navigates away and comes back
Proved a way to save grids
Walls
- Place "walls" across grid lines
- Provide different wall symbols, incl. doors, windows, ...
Download grid as PNG