Add installation instructions to README.
Add installation instructions to README.

HAPPY 100 COMMITS EVERYONE!

knewter/dogma,aerosol/dogma,eksperimental/dogma,jacknoble/dogma,5thWall/dogma,meadsteve/dogma,simonewebdesign/dogma,timbuchwaldt/dogma,linearregression/dogma,rrrene/dogma,henrik/dogma,iszlai/dogma