Discord bot: announce each new volunteer and the ancestor

[loredanacirstea]

Listen to the RegisterVolunteer event on the blockchain and post a message on Discord with this announcement:

Tentative volunteer registered: <USERNAME>, <ETHEREUM_ADDRESS>. Ancestor: <ANCESTOR_USERNAME>, <ANCESTOR_ADDRESS>.
Tx: https://rinkeby.etherscan.io/tx/<TRANSACTION_HASH>

Add event watcher, similar to watching for new registered tasks:

monitoring-bot/src/watch.js

Lines 30 to 33 in 06b6481

	function watchTasks (web3, thelaurel, lastBlock, callback, milliseconds) {
	console.log('---- monitor watchTasks');
	return watchEvent(web3, thelaurel, 'RegisterTask', lastBlock, callback, milliseconds);
	}

and

monitoring-bot/src/watch.js

Line 49 in 06b6481

const unsubscribeTasks = await watchTasks(web3, thelaurel, lastBlock, async (taskEvent) => {

, for building the data used in the message.

The actual message is formed in the bot.js file, similar to

monitoring-bot/bot.js

Lines 149 to 163 in 06b6481

	function onTaskEvent (task) {
	const etherscanlink = `https://rinkeby.etherscan.io/tx/` + task.transactionHash;
	let msg_discord = `**Task registered by ${task.organizerData} - ${displayLaurelAmount(task.task.amount)} ${task.laurel}**
	${task.gitHubIssue ? 'Url: ' + displayIssue(task.gitHubIssue) : 'ID: ' + task.taskid}
	Tx: <${etherscanlink}>
	`
	const msg_twitter = `Task registered by ${task.organizerData} - ${displayLaurelAmount(task.task.amount)} ${task.laurel}
	Tx: ${etherscanlink}
	${task.gitHubIssue ? 'Url: ' + displayIssueTwitter(task.gitHubIssue) : task.taskid}
	`
	msg_discord = task.gitHubIssue ? (msg_discord + `Claim Url: <${LINK_CLAIM}&issue=${task.gitHubIssue.number}>`) : msg_discord;
	console.log('-----onTaskEvent', msg_discord);
	return postMessage(msg_discord, msg_twitter);
	}