load config.yml pre-processed - add developer info to README.md

* modification to config/application.rb loads config/config.yml pre-processed - allowing cross-development of the various forks which have drifted out of compatibility (switchable in config/config.yml and config/database.yml - [see here for example](https://github.com/bits4commits/bits4commits/blob/master/config/config.yml))

* developer README contains install instructions and also some tentative contribution guidelines (ADMIIN: plz review/modify/remove)


this is the equivelant for this repo of a similar [commit to the peer4commit fork](https://github.com/sigmike/peer4commit/pull/105)