Add error message for invalid mount paths when adding secrets to an application

Fixes openshift#2073

Author: jeff-phillips-18

app/views/directives/add-secret-to-application.html

@@ -67,6 +67,11 @@ <h3>Add to Application</h3>
                   The mount path is already used. Please choose another mount path.
                 </span>
               </div>
+              <div class="has-error" ng-show="addToApplicationForm.mountVolume.$error.pattern && addToApplicationForm.mountVolume.$touched">
+                <span class="help-block">
+                  Mount path must be a valid path to a directory starting with <code>/</code>.
+                </span>
+              </div>
             </div>
           </div>
         </div>

dist/scripts/templates.js

@@ -5607,6 +5607,11 @@ angular.module('openshiftConsoleTemplates', []).run(['$templateCache', function(
     "The mount path is already used. Please choose another mount path.\n" +
     "</span>\n" +
     "</div>\n" +
+    "<div class=\"has-error\" ng-show=\"addToApplicationForm.mountVolume.$error.pattern && addToApplicationForm.mountVolume.$touched\">\n" +
+    "<span class=\"help-block\">\n" +
+    "Mount path must be a valid path to a directory starting with <code>/</code>.\n" +
+    "</span>\n" +
+    "</div>\n" +
     "</div>\n" +
     "</div>\n" +
     "</div>\n" +