Add a DOCKERFILE

HI! I've made a simple DOCKERFILE to create a container to run the server, as an alternative way for my Linux environment. This way should also be compatible with Windows and Mac.

I've also made a script to stop/remove container, rebuild the image and start again.

https://github.com/sergius02/surfingkeys-conf/commit/92cab14bb19304069024d353b37ced8cc0bba218