skip git clean if there is no .git directory
opennms-rrd-converter improvement.

As an optional step, you can now remove the old JRBs (single-metrics)
and the temporal files generated during the conversion.
opennms-rrd-converter improvement Part-II.

Re-implemented the method to find single-metric files. The candidates to
be removed are the files on which the file name is equal to the only one
single DS defined inside of it.
Merge remote-tracking branch 'origin/1.10' into 1.12
Added properity to disable the scanning of updated nodes from an import of a requisition.
NMS-6040
http://issues.opennms.org/browse/NMS-6040

Conflicts:
	opennms-provision/opennms-provisiond/src/main/java/org/opennms/netmgt/provision/service/Provisioner.java
Merge remote-tracking branch 'origin/1.12'

Conflicts:
	opennms-provision/opennms-provisiond/src/main/java/org/opennms/netmgt/provision/service/Provisioner.java