fix example: wrap dict.values in list()

In Python 3, `dict.values` returns a dict_values object, which does not support indexing.

Drop support for EOL Python 2.6, 3.2 and 3.3

Add <wbr> to definitions.py

Added to MediaWiki in ff74113bea (T54468).

Also removed the max cycles stop-gap, allowing much more complex pages
to be parsed quickly without losing nodes at the end

Also fixes #65, fixes #102, fixes #165, fixes #183
Also fixes #81 (Rafael Nadal parsing bug)
Also fixes #53, fixes #58, fixes #88, fixes #152 (duplicate issues)

rewrite and extend Caveats

>not supported, since they cannot be represented in the node tree.
It's not that they cannot be represented, it's that they would have to be evaluated.

"inherent limitation in wikicode" sounds misleading it's about generating an AST instead of HTML.