TimeLine window pulldowns work sorta (for the options that were coded :)
Still trying to bring back code without recoding uiDefButs. In future these
will get directly operator stuff linked. For time being made a simple
operator call function, like:
WM_operator_call(C, "ED_MARKER_OT_add");
and for forcing operator to run in the main region-window:
WM_operator_call_rwin(C, "ED_MARKER_OT_add");
These calls also work for modal operators, like marker grab in this case.