TODO Convert from a government structure. TODO Really need to have the value for previous, which is the writer register.
function Proposer (paxos, promise) {
    this._paxos = paxos
    this.collapsed = true
    this.promise = Monotonic.increment(promise, 0)
    this.proposals = []
    this.register = {
        body: {
            promise: paxos.log.head.body.promise,
            body: paxos.log.head.body.body,
            previous: paxos.log.head.body.previous
        },
        previous: null
    }
    this.proposal = null
}