Remove PYVER.to_str() from Assembler get().

Add assembler tests for non-ascii strings.
Add test for html escaping non ascii.
Add tests for html parsing non ascii.
Call IrcHTMLParser in tests the same way it's called in the code.
Test key generation with non-ascii nicks.
Fix class and test name.
Test IrcContext repr with non-ascii.
Call PYVER.to_str in IrcContext __repr__().
Make buffers an attribute in mock weechat.

So it can be modified in tests.
PYVER.to_str before writing trusts to file.
Test complete OTR session with non-ascii characters.
pylint whitespace recommendations.