[RFC] msvcrt: Implement _mbcjistojms

[David Hedberg]

Hello,

This function is supposed to convert a jis-encoded (Japanese)
character to sjis encoding. I think I botched my last attempt up in
more than one way so I've now reworked it slightly and thought I'd try
again, but perhaps I should first ask if there is anything else
obviously wrong with it.

For example, the implementation is a bit of a (as far as I can tell
working) black box, and the test of it basically tests two different
things depending on the codepage, which I am not sure is a good thing.

A very insignificant patch perhaps, but all comments are welcome. :)

--
David