allow friendly ids (vanity urls/slug) for teams

[mooreniemi]

instead of http://localhost:3000/teams/1/trends we'd have http://localhost:3000/teams/aztec/trends or http://localhost:3000/teams/the-friendly-toast/trends

may want to consider removing teams/ as a namespace and instead just have team names ie: http://localhost:3000/red-pandas/trends

obviously this brings up "no two teams can have the same name" but that'd be a punted concern to organization level separation (no two teams for zipcar could have same name) so you'd perhaps move eventually to http://localhost:3000/zipcar/aztec/trends

[jbrunton]

For real.