Fixes a bug if OPENNMS_HOME is not set in the environment

Another fix that primarily targets older releases.
Big thanks to @dschlenk for the catch and the PR.

Fixed an arithmetic error

Fixed an arithmetic error which caused pollsCompletedPerSec to be off by quite a lot. On instances doing RRD persisting, the value of metricsPersistedPerSec was impacted by an equivalent arithmetic error.

Thanks to David Hustace for noticing that the polls-per-sec figures looked suspiciously low.

A release of 1.4, built for old OpenNMS instances using OSGi 5

1.4-osgi5

Merge branch 'main' into features/osgi-5

A release of 1.3, built for old OpenNMS instances using OSGi 5

This release incorporates all fixes included in the main 1.3 release, but will run only on older OpenNMS releases (e.g. Meridian 2017) which use OSGi 5 instead of the newer OSGi 6.

Small fix to original release

Fixed a problem when we encounter a NaN in one of the stats, which probably happens only on very idle systems that haven't been running for very long.

First version distributed to users

This release is the first version distributed to users.