Install and fixup the plugins in the right location for Mac bundles
Install and fixup the plugins in the right location for Mac bundles

Make a list of the full path names of all the AvogadroLibs_PLUGINS
targets.

Then tell install_qt4_executable the list of plugin files, and
the place inside the bundle to put them.

Change-Id: Id5452405ff715ddcac738ed00fad5ce1fef2f939

OpenChemistry/avogadroapp,ghutchis/avogadroapp,OpenChemistry/avogadroapp,wadejong/avogadroapp,OpenChemistry/avogadroapp,wadejong/avogadroapp,OpenChemistry/avogadroapp,ghutchis/avogadroapp,wadejong/avogadroapp,ghutchis/avogadroapp,ghutchis/avogadroapp