Reduced role for Rhys

Some of you may have noticed that I have been reducing my work on
Portable.NET lately.  After nearly four years (in January), I'm a
little tapped out on new ideas.

Despite that, Portable.NET continues to develop at a good rate.  The last
two releases were almost exclusively done by contributors, and the work
has been first rate.

I plan to continue on in a supervisory capacity on the project in the
near future, but not in active day to day development.  I believe that
the project is now in good hands.

Cheers,

Rhys.