Merge pull request #136 from vincent-zurczak/master

Completely switch to OSGi
Work on deployment targets
#137 The target API needs to be reviewed
#97 Reintroduce the support of Neutron
#95 Do not wait in OpenStack if no Volume to attach and no Floating IP
#52 Support concurrent deployment of Openstack VM
#103: root instances must be associated with the 'target' installer
#101 Signal inexisting components when parsing instance definitions
#110 Check the resolution of component names