1 - Ensure TT doesn't try and call methods instead of VMethods
4 - Fix concatenating undef to HTML::String values.
7 - Fix concatenating strings that evaluate to false in a boolean context.
10 - Optimise _hsv_dot since it gets called heavily by HTML::String::TT
13 - Localize $@ in isa and can in case of modules that mishandle eval {}
14 - Support for single quotes (' to ')