Previously on non Windows Platforms the Programm would not get its
icon, as the *.rc is not used on e.g. Linux.
Use an xpm File for non Windows Platforms. Use the convenience macro
from wxWidgets to load the icon in a single call.
The icon was converted using GIMP 3.0.6. To avoid `-Wwrite-strings` the
static char* was converted to a const char*.
ScEd: Compilation fixes.
Atlas: Screen-space to world-space conversion when editing terrain.
Wireframe option. Minor wxWidgets 2.6.1 fixes. AoE3Ed.
This was SVN commit r2698.
