Improve dialog layout and fix UI policy issues with all of the dialog
boxes in the common, 3D viewer, CvPcb, and Eeschema code paths.
Updated the use of component to symbol.
* Add a Help button and text to the 3D alias configuration dialog
* Display KISYS3DMOD and internally defined KiCad path env vars
* Add a button to bring up the "Configure Paths" (env vars) dialog
* Remove the file name mapping feature from the resolver; this results in
the resolver always using the current definition rather than a possibly
outdated cache value.