Blender Git Loki

Add operator for toggling cmd box on Windows.

Use through search menu (Toggle System Console) or
call bpy.ops.wm.toggle_console().

This is based on patch [#6927] Optional Console for Windows
by Fahrezal Effendi, submitted on July 10th, 2007 (!)

This paves the way for adding a command-line option to Blender to
toggle this cmd console, and for having a user preference option
for this. Command-line option I haven't added yet, as there seemed
to be problems with Python interpreter initialization (read: crashes).

This works by redirecting stdout and stderr to blenderlog.txt in user
temp directory (most likely %TEMP%blenderlog.txt). When python problem
is fixed we can use this to always redirect stdout and stderr to this
logfile, making it also easier for us to ask users for this file in
bugreports.