Day of the Diesels

This release adds:

• Support for collectionFormat, closes #61 in #207
• Form encoder #211
• clojure.datafy/nav-ize the routes when martian.core/explore-ing #202 thanks to @danieroux

This release improves:

• Correctly identifies required nested objects #197
• Qualify js/Number to fix compiler warning #199
• Ensure graceful failure for implementation-specific objects that vcr writes but can't read back #205 thanks @lvh