control verbose mode in Portfile?

[René J. V. Bertin]

Christopher Jones wrote:

> If you want pass a message on to the user, you should not use verbose output
> to do that. Instead just use a regular ‘ui_msg'

Except that this is not what I'm after; `port -v` generates additional output to 
what's printed via `ui_msg`, just like `set -x` shows more than just the `echo` 
commands. I probably shouldn't have implied that I wanted to use this to give 
more feedback to the user, although it could be useful if the post-activate 
calls a command (say a scan) that generates informative output (say progress 
info).

A similar argument (irrelevant here) goes for `notes` vs. `ui_msg`: they're 
complementary. 

R