fix Honeynode issues with fluorine

- solve the OpenEXI compability with honeynode with a patch to
netconf-netty-util module
- solve the rpc 'get-schema' error by putting a netconfState info in the
OPERATIONAL datastore and copying in a dedicated folder all the yang
schemas needed at honeynode start-up (similarly to testtool)
- move device datastore config listener from core module
'minimal-distribution-core' to 'honeynode-plugin-impl' module.

JIRA: TRNSPRTPCE-32
Change-Id: I9af0ec2e098271a18993433cf99db9b3b5f73b20
Signed-off-by: Martial COULIBALY <martial.coulibaly@gfi.fr>