Fix warnings from `readr`.

Hotfix to address #40.

Metadata Support & Improved Internals

New Features:

• fetch metadata with quandl_datatable_meta()

Breaking Changes:

• quandl_api_key() is now quandl_key_set()

Other Changes:

• internal API-wrapping code has been rewritten and no longer depends on the Quandl package

Initial w/ Fixed Batching

Fixed some important bugs when batching requests.

Initial Release

The first working and tested version of tidyquandl!