Charset: Alias __repr__ to __str__ for debugging.
header_encode(): When calling quopriMIME.header_encode(), set
maxlinelen=None so that the lower level function doesn't (also) try to
wrap/fold the line.
encoding flag SHORTEST means to return the shortest encoding between
base64 and qp. This is used for the header_enc for utf-8. SHORTEST
isn't legal for body_enc.
Also some code cleanup:
- use True/False everywhere
- use == instead of `is' in a few places
- added _unicode() and make consistent the "is unicode" checks
- update docstrings
non-us-ascii character sets in headers and bodies. Some API changes
(with DeprecationWarnings for the old APIs). Better RFC-compliant
implementations of base64 and quoted-printable.
Updated test cases. Documentation updates to follow (after I finish
writing them ;).