Add "Launch OS App Now" and "Install Shortcuts" checkboxes to installer

[macumber]

Enhancement Request

Add "Launch OS App Now" checkbox to installer. Also add an "Install Shortcuts" checkbox to installer.

Detailed Description

This would make it easier for new users who might not know how to navigate to the install directory and find the exe to launch.

Possible Implementation

https://forum.qt.io/topic/80203/how-to-launch-my-software-when-the-installation-is-finished-qt-installer-framework https://doc-snapshots.qt.io/qtifw-master/qtinstallerframework-startmenu-example.html