Checkpoint. 218 tests are okay; 53 are failing. Done so far:

- all classes are new-style (but ripping out classobject.[ch] isn't done)
- int/int -> float
- all exceptions must derive from BaseException
- absolute import
- 'as' and 'with' are keywords

sysconfig.py

@@ -16,7 +16,7 @@ import re
 import string
 import sys
 
-from errors import DistutilsPlatformError
+from .errors import DistutilsPlatformError
 
 # These are needed in a couple of spots, so just compute them once.
 PREFIX = os.path.normpath(sys.prefix)