Merge pull request #3 from mstilkerich/master

Autodiscovery using DNS SRV/TXT records
fix FS#90: show correct count in contact groups
fix FS#89: add new user to selected group, if any
add composer.json in preparation for plugins.roundcube.net
fix code folding on some functions
check necessary amount of parameters to debug_backtrace to stay compatible to PHP 5.3
give complete path to check for config.inc.php
Merge branch 'dev' of github.com:blind-coder/rcmcarddav into dev
Merge remote-tracking branch 'upstream/dev'
fix a typo