mikel/mail — pull request #361 by bogdan (2012-02-22 09:47:05+00:00)
Title: Support 8bit encoding for ruby 1.9

One of the email I work with have the following sequence in body:

```
=?8bit?Q?ALPH=C3=89E?=
```

8bit encoding in mail should be converted into `ASCII-8BIT` in ruby.
This is kinda no doubt change.

Also this string is really UTF string, but encoding is set to 8bit maybe because it came from some serial device like network printer.
That is why there is also some rescue code in this PR:
When 8bit encoded string can not be encoded to UTF-8, we can at least convert it to UTF manually.

For Ruby1.8 this works, I just didn't have a chance to run test suite on ruby 1.8 because of #360.