Various tweaks for myplc-native (not thoroughly tested yet) :

Various tweaks for myplc-native (not thoroughly tested yet) :
. doc packaging in myplc-native as well, for both myplc and plcapi
. default value for *_IP variables are now empty;
  should result in more accurate /etc/hosts and other config-generated files
. gethostbyname uses python rather than perl (hope this shrinks deps)
. make sync now works towards vserver-based myplc only