Added test for unicode basic authentication
Python 3 compatible string handling
Switched to bytes
Subclass HTTPBadCSRFToken from HTTPBadRequest and have request.session.check_csrf_token use the new exception.

This supports a more fine-grained exception trapping.
Merge branch 'master' of github.com:Pylons/pyramid
Merge branch 'check_csrf_token' of kpinc/pyramid into feature.bad-csrf-token-exception
move HTTPBadCSRFToken to p.exceptions.BadCSRFToken
update doc references
Merge branch 'master' of Cuidightheach/pyramid into fix.basic-authentication-encodings
attempt to decode basic header as utf-8 and fallback to latin-1

fixes #898
fixes #904
update changelog
fix tests on py3
modify the docs for the renderer interfaces
link to the public renderer interfaces
Merge branch 'feature.signed-cookie-session'
fix merge conflict
Merge branch 'feature.bad-csrf-token-exception'
Merge branch 'master' into fix.basic-authentication-encodings
Merge branch 'fix.basic-authentication-encodings'
add a note so we can defend the choice later