Fix types of WebApiController

POST expects to have an object passed in.
Allow DELETE of votes (without ID)

This allows us to clear out a vote set, thereby resetting the voting
session.
Basics for the Admin Panel front-end

Adds a big button to reset the votes, and all the files required by the
new View.
Hook it up

Makes the button call "DELETE /api/vote" to remove all votes.
The button changes text and becomes disabled on clicking, to give feedback
that the process has worked.
Allow DELETE by id on Votes

Allows for a single vote to be deleted.
Hook up single-vote deletion

Adds the option to delete a single vote to the admin panel, via a votes
table.
Resize results by Vote count

Keeps the size of the chart bars (roughly) constant and makes the chart
bigger, rather than keeping the chart size constant and shrinking the
bars.
Merge pull request #13 from tpkelly/feature/admin-panel

Admin Panel