* remove 2/3 shims in pygments.util
* update setup.py metadata

The ansi color names are changed to names which are easier to understand and align with color names of other projects and terminals. (e.g. ``#ansifuchsia`` to ``ansibrightmagenta``)

This also drops the # prefix to the color names. Hashtag # is usually used for hex colors and the names are already prefixed with `ansi`. Furthermore, it allows the new and old set of names to be exclusive.

This introduces support for some missing features to the Handlebars lexer:
Partials and path segments. Partials mostly appeared to work before, but the
`>` in `{{> ... }}` would appear as a syntax error, as could other
components of the partial. This change introduces support for:

* Standard partials: `{{> partialName}}`
* Partials with parameters: `{{> partialName varname="value"}}`
* Ddynamic partials: `{{> (partialFunc)}}`
* Ddynamic partials with lookups: `{{> (lookup ../path "partialName")}}`
* Partial blocks: `{{> @partial-block}}`
* Inline partials: `{{#*inline}}..{{/inline}}`

It also introduces support for path segments, which can reference content in
the current context or in a parent context. For instance, `this.name`,
`this/name`, `./name`, `../name`, `this/name`, etc. These are all now tracked
as variables.