Add mention of app_config.yml to readme
Add mention of app_config.yml to readme

Flaburgan/diaspora,diaspora/diaspora,Muhannes/diaspora,diaspora/diaspora,SuperTux88/diaspora,SuperTux88/diaspora,jhass/diaspora,geraspora/diaspora,geraspora/diaspora,Flaburgan/diaspora,Amadren/diaspora,diaspora/diaspora,despora/diaspora,Amadren/diaspora,geraspora/diaspora,despora/diaspora,Amadren/diaspora,spixi/diaspora,KentShikama/diaspora,Flaburgan/diaspora,SuperTux88/diaspora,jhass/diaspora,Flaburgan/diaspora,Muhannes/diaspora,Amadren/diaspora,spixi/diaspora,Muhannes/diaspora,spixi/diaspora,spixi/diaspora,jhass/diaspora,KentShikama/diaspora,despora/diaspora,geraspora/diaspora,KentShikama/diaspora,KentShikama/diaspora,jhass/diaspora,despora/diaspora,diaspora/diaspora,Muhannes/diaspora,SuperTux88/diaspora