* This is a possible fix for a case where render work triggered by mouse
movements (such as pixel and vertex picking) can happen faster than it
executes, leading to a backlog of render commands and a noticeable lag
which only gets worse the more you move the mouse until everything
seems to be unresponsive or laggy (especially if you then trigger a
blocking command like event change, which will block the whole UI
until the queued picks happen).
* Since a new pick coming in will override and make redundant the
previous pick, we allow the render commands to do just that. If a new
command comes in, we remove any previous commands with the same tag
and put the command in the first match (this prevents a tagged invoke
always being pushed to the back of the queue).
* The option will enable monospaced fonts for all data displays, like
the list of events, API calls, etc as well as pipeline displays, entry
of filename/directory in the capture window and many other places.
Pure UI labelling etc mostly still stays as a serif font.
* A few sizes of controls were tweaked (like headers in the pipeline
windows) so that they didn't just barely overflow with the larger
font.
* While looking at this, it became obvious that buffer viewers and
constant bufferviewers should always display in monospaced regardless,
so that has been changed.
baldurk