Adjust Various install stuff.
Summary:
- Use KDE install targets to (fixes installing to non kde dir) - Thanks @krop
- Sync to style
- Add build option "DEPLOY_PLUGINS_WITH_BINARY" to install plugins at bin/plugins
- Updated plugin search path for new core folder
- Added check at InstallPrefix/KdePluginDir, this helps programs not installed within the same prefix to find the plugins.
- Allow plugin check to happen on all oses.
- Update Build docs with new information
Reviewers: tcanabrava, patrickelectric, laysrodrigues
Reviewed By: tcanabrava
Subscribers: Atelier: AtCore
Tags: Atelier: AtCore
Differential Revision: https://phabricator.kde.org/D13212