Add Gifs to Documentation

[john-science]

It would aid newcomers to the project if there were gifs of each of the maze-generating and maze-solving algorithms.

This suggested by @ondras in a ticket in ROT.js ondras/rot.js#76

[john-science]

The process seems clear. Temporarily alter the maze-generating/solving algorithms to output the maze grid at each time step, and save those grids to pngs as in the documentation:

https://github.com/theJollySin/mazelib/blob/master/docs/EXAMPLES.md#example-2-plotting-the-maze-with-matplotlib

Then glue those PNGs together into GIFs:

http://unix.stackexchange.com/questions/24014/creating-a-gif-animation-from-png-files

[john-science]

Well, the generators have had gifs added to them. But are gifs the best solution? There aren't many options, when it comes to plain GitHub Markdown. Pausable gifs would be better. Probably html5 video would be ideal.