re-integrate SWT marker recording w/ userconfig param to switch from vanilla

[indig0fox]

userconfig hpp file to include variable for marker types
"VANILLA"
"SWT_MARKERS"

Marker event calls should then follow this choice.
Potentially for future, integrate SWT marker polyline/rect/ellipse drawing if able.

[Zealot111]

@indig0fox @fank can we provide swt_markers.pbo which will have infrastructure to save markers via ocap.pbo to not look for exotic ways to intercept markers placed via swt_markers?
(as we with @tekig did in our old repository)
In this case solution would be simple.