allow complex param names

[spacedevin]

• currently we only support params like /item/:id/edit
• it would be nice to allow something like /item-:id/edit, perhaps wrapping like /item-{:id}/edit

[spacedevin]

Triaged for Tipsy 2.0 (#57)

Still open. 2.0 tightened :param to a single path segment ([^/]+). Inline forms like /item-{:id} are not supported — use a raw regex route for now.