feat: Create OutputAudio model

see: #10

server/models/OutputAudio.js

@@ -0,0 +1,28 @@
+const mongoose = require('mongoose')
+
+let OutputAudioSchema = new mongoose.Schema(
+	{
+		text: String,
+		title: String,
+		author: {
+			type: mongoose.Schema.Types.ObjectId,
+			ref: 'User'
+		}
+	}
+)
+
+OutputAudioSchema.methods.addAuthor = (author_id) => {
+	this.author = author_id
+	return this.save()
+}
+
+OutputAudioSchema.methods.getUserInputAudio = (_id) => {
+	OutputAudioSchema.find({'author': _id}).then((audio) => {
+		"use strict"
+		return audio
+	})
+}
+
+module.exports = mongoose.model('OutputAudio', OutputAudioSchema)
+
+