Fix Custom Field Definitions

• Fix custom field definitions from single items to collections (#49)
• Fixing the build

OK, let's launch!

Didn't seem to trigger launch activity last tag, but then again, that was the day of S3 being down, so let's try again.

Support for Asana sections and Boards views

This version adds support for the Sections resource and includes features for working with Boards layouts in Asana (for example, adding the layout field to the Projects resource to indicate whether a project is viewed as a board or a list).