sample.py: 1st cut at Sample.download.
annotation.py, sample.py: remove class_url and get from APIResource.
errors.py: store actual request.
client.py: add allow_redirect parameter
Try delegation of Annotation.all and Sample.all
resource.py -> apiresource.py
Sample and Annotate code now inherits corresponding API classes
apiresource.py: create Download and Upload API resources.
test_sample.py: Test sample download.
__init__.py: switch to restructured doc format
Need to skip if we can't access any samples.
Wrong inheritance for annotation. Add annotation download test.
Grammar typo
Misc little things from dave's review
Misc changes Dave's review part 2
Avoid lint error in long line
Merge pull request #36 from solvebio/feature/annotate-download-part2

Feature/annotate download (part 2)