Polls - AgoraVoting

[voodoorai2000]

What

Make AgoraVoting an optional component

Why

AgoraVoting is a fantastic system for secure voting.
However it's not trivial to setup. We should be able to switch between using AgoraVoting and the standard voting system Poll::Voters

How

• Addding a setting to decide what voting system to use
• Reactivating all selenium specs, which test AgoraVoting (hard, we need to setup an Agoravoting instance at IAM)
• Making sure both systems work with the rest of Poll's functionalities (Results, Stats)

Where

Poll::Nvotes