Tons of UI and code cleanups, renamed many sql tables and fields, started adding created_at and updated_at fields

add_vendor_modal.php

@@ -8,6 +8,7 @@
         </button>
       </div>
       <form action="post.php" method="post" autocomplete="off">
+        <input type="hidden" name="client_id" value="<?php echo $client_id; ?>">
         <div class="modal-body bg-white">
 
           <ul class="nav nav-pills nav-justified mb-3" id="pills-tab" role="tablist">