PwMoviePlayer improved, static builds made easy in Xcode

Command line arguments to PwMoviePlayer have been implemented to make it easy to run and script for demo purposes. New options are:
-f movieFile
-l legendFile
-e endFrame
-r frameRate

In addition, the Xcode project has been modified to support easy static builds. The Xcode project now requires QTS and GSL source tree variables (in addition to the previously required QT).

The Polyworld installation and build web page has been updated with instructions to match this 1.5.2 release. See:
http://beanblossom.in.us/larryy/BuildingPolyworld.html