Added image saving to rune drawing

Now drawing a rune creates the file "MyFile.png" which shows the
registered mousepositions.

Things that need to be done:
- Change the way the rune class exists? Initiate a rune with an array as
opposed to "dynamically"
- Resize the image/rune to a uniform size (so that comparisons can
feasibly be made)
- Add comparator method (yeah this is a bigun son)
- Add rune "models" (ie, what you are striving for).
Merge branch 'master' of https://github.com/fjafjan/Game