log CONTRIBUTING @ 4987:8a8ec909ac20

age author description
2015-08-31 Kim Alvefur CONTRIBUTING: Run through pandoc to normalize markdown syntax
2015-08-31 Kim Alvefur CONTRIBUTING: Update guidelines and URL to hg repo
2015-04-09 Kim Alvefur Add README and CONTRIBUTING files containing the text from https://code.google.com/p/prosody-modules/