many users of the markup property are not interactive text cases, so splitting
off the interactive methods resolves a number of unimplemented method issues
ref T5719
Differential Revision: https://phab.enlightenment.org/D7787
Adds basic markup operations for text objects, and implements it in
Efl.Canvas.Text.
Also, this adds the Efl.Text.Markup_Util class.
This utility class allows basic text-markup conversions.
@feature