Request negotiated rates from UPS
Expanded to support multiple packages per request, and now more object oriented.

USPS still provides the cost of each package back individually, so we sum those up per service requested
Update read me
Streamlined the packaging stuff with some reasonable assumed defaults for now
Readme update
Provide rate quotes back as objects
Updates to the documentation example return values
Change to the carbon dependency
Specify the container based on the package size
Merge branch 'master' of github.com:pdt256/shipping

Conflicts:
	src/Fedex/Rate.php
	src/UPS/Rate.php
	src/USPS/Rate.php
	tests/ShipTest.php
Drop Carbon requirement
Merge pull request #3 from troydavisson/master

Looks good. Thanks!