Issue Cleanup v0.14.4

Merge pull request #159 from lawinslow/master

Addressing issue #158

Bugfixes

Improvements to back-end bugs to address several issues. No changes to interface.

Better interface

Includes introduction of sbitems as S4 objects, better error checking for API calls, and refinements to make the interface more internally consistent. Expect additional updates soon.

August Release

Merge pull request #100 from lawinslow/master

fixed some missing files and issues with tests

Mid-July release

v0.11.5

patch version increment

March updates release

Merge pull request #44 from lawinslow/master

Fixed up documentation a bit

early release for sbtools

Merge pull request #33 from jread-usgs/master

Fix for error catch (dup of item_get)