Allow multi-voting but with vote limit in proposals

[thomasgwatson]

Initial proposals implementation allows for:

• one user, one vote, and
• one user, can vote once for each proposal option

In other voting use-cases, users should be able to:

• vote for many options but still have a limit to the number of votes
• vote for many options, with a limit for votes but also be able to vote for an option more than once

This ticket is for the implementation of those extra use-cases.