New extension to support problematic MBCS on Windows.
The aim of this extension is to clear the problem related to having
0x5c in 2nd byte of encoded bytes. So this extension is usefull for:
* Japanese Windows user shift_jis encoding.
* Chinese Windows user using big5 encoding.
To use this extension, simply enable it without any customization.
Note that some important python built-in functions and mercurial
functions are altered for this extension to convert argument if need
to handle MBCS.
% basic
% unknown
*** [alias] unknown: command bargle is unknown
% ambiguous
*** [alias] ambiguous: command s is ambiguous
% recursive
*** [alias] recursive: circular dependency on recursive
adding foo
% with opts
C foo