Fix YAML bad commented line
Use "resource" for the GLUE2GroupID

Altough using "cloud" would seem OK, we have to use "resource" so as to
get the information included in the site-BDII.

Refers #1
Do not set the GLUE2DomainID on the DN if not needed

The GLUE2DomainID=SITE in the DN is only needed if the node is also a
site-BDII so we should not set this if it is not needed.

Closes #1
Merge pull request #2 from alvarolopez/bug/1

Fix generated LDIF to be used with an existing site-BDII