Introduce new points-based table

Replaces the "Vote" button with a "- 0 +" button group, to increase or
decrease the points given to an option.
Add SessionPointsVoteController

Introduces a controller to handle getting all PointsVotes for a given
session. Currently all methods return MethodNotAllowed
Revert "Add SessionPointsVoteController"

This reverts commit c6e88995a75c8e95fe017a40688163945351ce81.
Add Value to Votes

Adds a "Value" category and defaults it to 1.
Different voting strategies can hijack this to use for their own ends
(such as ranks, points, etc.)
"PUT List<Vote>" instead of "PUT Vote"

Users can now vote for multiple items in a single session in some
Voting Strategies. When we PUT to create a vote, we need to push multiple
votes instead of just the one.
Enable increasing and decreasing of votes

Hooks in a new knockout array to represent the points per option, and
has the increase/decrease methods alter the value for a given row.

Adds limits to stop values from exceeding 3 points per vote, 7 points
total, or from becoming negative.
Glue it all together

Hooks up the back end to write the points votes to the database, and the
front-end to chart the results
Fix chart tooltip

Displays the number of points a single option has, with a list of who
voted for it.
Update with previous user votes

After logging in, the previously votes are added back to the pointsArray
and the buttons are updated as required.
Fix unit tests
Allow selection of voting strategy

Adds an option to the "Create Poll" page to pick the voting strategy.
We either use "Basic" for Single-vote, "Ranked" for STV, or "Points" for
the points-based votes.

We also catch any mail errors, and reject any empty-string destination
email addresses.
Update email links

The service is now hosted on "votingapp.", not "voting-app."
Don't require the partial js

We only ever need the partial js in one place, so we don't need to create
a shortcut for it.
Merge pull request #53 from tpkelly/feature/antelope

Points-based voting