Create a Proposal

function createProposal(address to, uint tokens, bytes metadataHash) public;

Creates a proposal to send the given amount of tokens to the given address, with details about the request in the metadataHash.

Emits the following event:

event ProposalCreated(uint proposalID, address proposer, address to, uint tokens, bytes metadataHash);

Return value: the identifier of the request being made, specified by requestID.