Work in progress on IL datasource
Add validation for sub-contest votes and unique candidates

Add validators that sum sub-contest votes and compare them against
known contest totals from the Maryland Board of Elections website.

I only wrote one validator per data file layout/loader class, but
I implemented some helper functions that should make it easy to
validate the totals for other elections.

Also add a validator that checks that there is a unique set of
candidates for each contest.

Addresses https://github.com/openelections/core/issues/36
Add results validator for 2010 general election

Addresses https://github.com/openelections/core/issues/36
added github data_url to url_paths
Merge branch 'dev' of github.com:openelections/core into dev
Merge branch 'dev' into il
Cleanup of Illinois datasource

The work in progress was in pretty good shape, but I added some
comments, properly set the filename extension and did some basic
handling of special elections.

Addresses https://github.com/openelections/core/issues/117
initial OH datasource work