GTK3: Switch to using CSS syntax for specifying fonts from Pango. Apparently the theme warnings produced on GTK3 were from using Pango syntax for specifying fonts, instead of CSS syntax. Can't find any information about when CSS syntax was introduced... So hopefully it works through the entire GTK3 series. Also fix some GCC warnings in the new dwtest code.

prefix=@prefix@
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${exec_prefix}/include
 
Name: dwindows
Description: Dynamic Windows Cross platform UI Toolkit
Version: @VERSION@
Libs: -L${prefix}/lib -ldwindows @LIBS@
Cflags: -I${prefix}/include @CFLAGS@ -D@DW_DEFINE@