18438 - application option parser boolean parsing not working

OptionParser supports boolean flags in the form --[no-]noop which when
called on the command line as --noop would set true and false when
called as --no-noop

We always set boolean flags to true and never supported the inverse mode
correctly, this commit handles that scenario
18437 - mco plugin doc broken for data plugins

In the past mco plugin doc failed when passing a data agent as the
parameter.

In this commit mco plugin doc will correctly display the meta and help
data for a data plugin.
18437 - mco plugin doc broken for data plugins

Update changelog
18259 - Release 2.3.0

 - Release notes and changelog tweaks
 - Update the Rakefile for 2.3.0-1