- Change the config variable name.
- The config variable no longer references ceilometer.
- It is now clearer that the config variable is for all plugins
- The variable is a noun instead of a verb, so it's clearer that
this is something to define, instead of a boolean.
- Update docs
- Added a clarification on the format of the custom unit definition.
- Corrected incorrect reference to COLLECTD_CEILOMETER_UNITS in
devstackGSG.rst and usage.rst
Closes-Bug: #1656877
Change-Id: Ie688397242d57cf0fee6629fafb89afd8899a599