22790 - Plugin packager doesn't apply --pluginversion option

In the past the plugin packager application had an available
--pluginversion option but the value was not passed down to the
packager.

This commit passes the value of pluginversion all the way down and
refactors the constructors of the definition classes making them more
maintainable.
Merge pull request #118 from ploubser/bug/master/22790

22790 - Plugin packager doesn't apply --pluginversion option