Add escape-function for identifiers

[gagge]

Today you need to do it like this.
There must be a better solution that doesn't need getConnection().

const db = require('larvitdb');
db.pool.getConnection(function(err, dbCon) {
	const sql = 'SELECT * FROM users WHERE username LIKE ' + dbCon.escapeId(postData);

	dbCon.query(sql, function(err, rows) {
		dbCon.release(); // Always release your connection when the query is done

		if (err)
			throw err;
	});
});