HPCC-11108 DOCS:Nagios

Fix HPCC-11108 DOCS:Nagios
Provide documentation about Nagios
and HPCC Reporting AND Monitoring
added Nagios content.

Signed-off-by: g-pan <greg.panagiotatos@lexisnexis.com>

@JamesDeFabia @garonsky please review
Is the deletion of this file (docs/wip/ECL_Watch.xml) part of the Pull request?