pip install toga gives error in Python3 virtualenv

[jtauber]

Due to the L in /toga/platform/win32/libs/constants.py line 533 it appears

$ pip install toga
Downloading/unpacking toga
  Downloading toga-0.1.0-py2.py3-none-any.whl (526kB): 526kB downloaded
Downloading/unpacking cassowary (from toga)
  Downloading cassowary-0.5.0.tar.gz
  Running setup.py (path:/Users/jtauber/Development/VirtualEnvs/toga-test/build/cassowary/setup.py) egg_info for package cassowary

    warning: no files found matching 'requirements*.txt'
Installing collected packages: toga, cassowary
*** Error compiling '/Users/jtauber/Development/VirtualEnvs/toga-test/build/toga/toga/platform/win32/libs/constants.py'...
  File "/Users/jtauber/Development/VirtualEnvs/toga-test/build/toga/toga/platform/win32/libs/constants.py", line 533
    MB_TOPMOST = 262144L
                       ^
SyntaxError: invalid syntax

  Running setup.py install for cassowary

    warning: no files found matching 'requirements*.txt'
Successfully installed toga cassowary
Cleaning up...

[freakboy3742]

This was addressed by #3.