Squashed 'CMakeModules/' changes from dd92677..2979d55

2979d55 Fix install when version string is empty.
e83ac80 Adds config installation to export_package.
10ad6e3 Adds export_package and PACKAGE args to def_*

git-subtree-dir: CMakeModules
git-subtree-split: 2979d55e3ab903070e022c1154acd1a4cf4517e0
Merge commit '537149e6fc0724195232dd3b46f9ff1a9b71ef50'
Adds export_package