0.12.2dev: improve e-mail notification for installations dedicated to CJK users.
0.12.2dev: improve e-mail notification for installations dedicated to CJK users.

Also introduce new `[notification] ambiguous_char_width` TracIni setting, with a default to `single`, which means no change from the current behavior. With `double` however, ambiguous characters (`east_asian_width(ch) == 'A'`) will count for two ASCII characters, as wide characters do, for the purpose of the e-mail layout computations.

Patch contributed by Jun Omae on #4717. Also thanks to Shun-Ichi Goto for his explanations and hints.

git-svn-id: 30ec3c1a2098df185a8733d0352d646269562639@10393 af82e41b-90c4-0310-8c96-b1721e28e2e2

exocad/exotrac,exocad/exotrac,exocad/exotrac,exocad/exotrac