Fix typos in README.md
Apply license AGPL-v3.0
Add readme
voronoi: remove generated file, prevent from happening again

gah, it happened again!
voronoi: brightness calculation is easier to read
webserver: adapt voronoi's api change
voronoi: fix u32 to u8 conversion bug

there's an option to brign it back
remove random images

sorry, my bad!
webserver: move defaults to voroi

all the defaults are defined in the voronoi crate, we just pass the
user's values to it, if the they specify some.

also add configurable (still hardcoded though) limit for bubbles
voroni: move default configuration to drawign function

let's define defaults in one place, that makes a lot of things easier.
webserver: let users control encoding quality
voronoi: save to png by default, it looks nicer
webserver: serve images with correct mime type
webserver: add a favicon
webserver: add restrictions and error messages

Prevent the client from creating requests that generate too much data or
take too many resources. The current restrictions are still generous.
Error messages explain when the client hit the restrictions or when
other things go wrong.
voronoi: Fix possible crashes

This commit rewrites parts of code that use .unwrap(). A black image is
generated when the given parameters don't make sense (ie num_points is
set to 0)
webserver: don't save files to a filesystem
voronoi: Fix cargo warnings
webserver: add dependency 'image'
webserver: adapt to changes in voronoi