Lists list and CUD

Custom forms list
Updated DB schema (not yet implemented in the server, which means that most of the server is not broken).
- custom forms are independent of a list
- order and visibility of fields is now in custom_fields
- first_name and last_name has been turned to a regular custom field

lib/dbcheck.js

@@ -5,7 +5,7 @@ This module handles Mailtrain database initialization and upgrades
 */
 
 let config = require('config');
-let mysql = require('mysql');
+let mysql = require('mysql2');
 let log = require('npmlog');
 let fs = require('fs');
 let pathlib = require('path');