Linter: Fix all lint errors

Signed-off-by: Philip Molares <philip.molares@udo.edu>

app.js

@@ -1,44 +1,44 @@
 'use strict'
 // app
 // external modules
-var express = require('express')
+const express = require('express')
 
-var ejs = require('ejs')
-var passport = require('passport')
-var methodOverride = require('method-override')
-var cookieParser = require('cookie-parser')
-var compression = require('compression')
-var session = require('express-session')
-var SequelizeStore = require('connect-session-sequelize')(session.Store)
-var fs = require('fs')
-var path = require('path')
+const ejs = require('ejs')
+const passport = require('passport')
+const methodOverride = require('method-override')
+const cookieParser = require('cookie-parser')
+const compression = require('compression')
+const session = require('express-session')
+const SequelizeStore = require('connect-session-sequelize')(session.Store)
+const fs = require('fs')
+const path = require('path')
 
-var morgan = require('morgan')
-var passportSocketIo = require('passport.socketio')
-var helmet = require('helmet')
-var i18n = require('i18n')
-var flash = require('connect-flash')
+const morgan = require('morgan')
+const passportSocketIo = require('passport.socketio')
+const helmet = require('helmet')
+const i18n = require('i18n')
+const flash = require('connect-flash')
 
 // core
-var config = require('./lib/config')
-var logger = require('./lib/logger')
-var errors = require('./lib/errors')
-var models = require('./lib/models')
-var csp = require('./lib/csp')
+const config = require('./lib/config')
+const logger = require('./lib/logger')
+const errors = require('./lib/errors')
+const models = require('./lib/models')
+const csp = require('./lib/csp')
 
 // server setup
-var app = express()
-var server = null
+const app = express()
+let server = null
 if (config.useSSL) {
-  var ca = (function () {
-    var i, len, results
-    results = []
+  const ca = (function () {
+    let i, len
+    const results = []
     for (i = 0, len = config.sslCAPath.length; i < len; i++) {
       results.push(fs.readFileSync(config.sslCAPath[i], 'utf8'))
     }
     return results
   })()
-  var options = {
+  const options = {
     key: fs.readFileSync(config.sslKeyPath, 'utf8'),
     cert: fs.readFileSync(config.sslCertPath, 'utf8'),
     ca: ca,
@@ -60,18 +60,18 @@ if (!config.useSSL && config.protocolUseSSL) {
 
 // logger
 app.use(morgan('combined', {
-  'stream': logger.stream
+  stream: logger.stream
 }))
 
 // socket io
-var io = require('socket.io')(server, { cookie: false })
+const io = require('socket.io')(server, { cookie: false })
 io.engine.ws = new (require('ws').Server)({
   noServer: true,
   perMessageDeflate: false
 })
 
 // others
-var realtime = require('./lib/realtime.js')
+const realtime = require('./lib/realtime.js')
 
 // assign socket io to realtime
 realtime.io = io
@@ -80,7 +80,7 @@ realtime.io = io
 app.use(methodOverride('_method'))
 
 // session store
-var sessionStore = new SequelizeStore({
+const sessionStore = new SequelizeStore({
   db: models.sequelize
 })
 
@@ -154,7 +154,7 @@ app.use(session({
 }))
 
 // session resumption
-var tlsSessionStore = {}
+const tlsSessionStore = {}
 server.on('newSession', function (id, data, cb) {
   tlsSessionStore[id.toString('hex')] = data
   cb()
@@ -246,9 +246,9 @@ io.sockets.on('connection', realtime.connection)
 
 // listen
 function startListen () {
-  var address
-  var listenCallback = function () {
-    var schema = config.useSSL ? 'HTTPS' : 'HTTP'
+  let address
+  const listenCallback = function () {
+    const schema = config.useSSL ? 'HTTPS' : 'HTTP'
     logger.info('%s Server listening at %s', schema, address)
     realtime.maintenance = false
   }
@@ -290,7 +290,7 @@ function handleTermSignals () {
   realtime.maintenance = true
   // disconnect all socket.io clients
   Object.keys(io.sockets.sockets).forEach(function (key) {
-    var socket = io.sockets.sockets[key]
+    const socket = io.sockets.sockets[key]
     // notify client server going into maintenance status
     socket.emit('maintenance')
     setTimeout(function () {
@@ -300,7 +300,7 @@ function handleTermSignals () {
   if (config.path) {
     fs.unlink(config.path)
   }
-  var checkCleanTimer = setInterval(function () {
+  const checkCleanTimer = setInterval(function () {
     if (realtime.isReady()) {
       models.Revision.checkAllNotesRevision(function (err, notes) {
         if (err) return logger.error(err)