Add Jessica B. Hamrick as a CONTRIBUTOR
Version 0.3.1

Better support to local data packages. Local paths do not behave
in the same way as urls (trailing backslash is different). This
version makes datapackage work in a more common sense way for
local data packages.
Fix bad email/web test
Merge pull request #15 from jhamrick/add-setters

Add setters (and some getters) for datapackage properties
Rename test.py to test_datapackage.py
Flesh out version verification
Add methods to bump the major, minor, and patch versions
Move SemanticVersion namedtuple constructor to module scope
Also move valid regex into module scope