Fix UnicodeError when givenName or sn Shibboleth Header contains unicode chars

Shibboleth Header values like Nicol\xc3\xb2  raise UnicodeError evaluating fullname 
This looks odd: you have put UTF8 byte values into a Unicode string that already has a Unicode codepoint in it.  Which should it be?  The two data strings are now:
```
jasön; John; bob; NicolÃ²
包; smith; ViganÃ²
```