- Update to version 3.3.29 
- Delete CONFLICTS, cad/gtkwave is no more 
- Port installs icons now, use INSTALLS_ICONS
- Use update-desktop-database to register filetype associations
PR: ports/163987 
Submitted by: maintainer 
Add GTKWave 3.1.9 port.
The 3.x train of GTKWave has significantly more new featured and bugfixes,
but would require introducing PORTEPOCH to replace cad/gtkwave.
[Timeout on feedback from cad/gtkwave maintainer.]