Peer dependencies and flexible names

Two quality-of-life changes: the packages now sit as peer dependencies so your project controls their versions, and variable names stopped being fussy about notation.

Improved

• Packages as peer dependencies. Styleframe packages are peer dependencies now, so your app owns a single resolved version of each instead of nested copies.
• Interchangeable variable notation. Dot notation and double-dash notation are now interchangeable in variable names — write whichever reads better; both resolve the same.

New

• Sitemap support and a fluid responsive design demo landed in the docs.

Fixed

• Utilities no longer emit a spurious default keyword.