fix slug validation pattern

(cherry picked from commit 564b275)

src/main/webapp/resources/js/admin/feature/organization-edit/organization-edit.html

@@ -27,13 +27,13 @@ <h2>Advanced Configuration</h2>
                 <span class="input-group-addon">
                     <span>{{$ctrl.baseUrl}}/o/</span>
                 </span>
-                <input type="text" id="slug" data-ng-model="$ctrl.organization.slug" class="form-control" pattern="^[A-Za-z0-9]{1,}([-_]*[A-Za-z0-9]+)+$" name="slug" data-ng-model-options="{updateOn:'blur'}"/>
+                <input type="text" id="slug" data-ng-model="$ctrl.organization.slug" class="form-control" pattern="^[A-Za-z0-9]+([\-_]*[A-Za-z0-9]+)+$" name="slug" data-ng-model-options="{updateOn:'blur'}"/>
                 <span class="form-control-feedback" data-ng-if="$ctrl.loading"><i class="fa fa-circle-o-notch fa-spin"></i></span>
                 <span class="input-group-addon">
                     <span>/</span>
                 </span>
             </div>
-            <field-error class="text-danger" data-field-label="'URL'" data-form-obj="$ctrl.insertNewOrganization" data-field-obj="$ctrl.insertNewOrganization.slug" data-min-char="3"></field-error>
+            <field-error class="text-danger" data-field-label="'URL'" data-form-obj="$ctrl.insertNewOrganization" data-field-obj="$ctrl.insertNewOrganization.slug" data-min-char="3" data-required-pattern="'A-Za-z0-9_- (no spaces; first and last characters must be a letter or a number)'"></field-error>
         </div>
         <div class="form-group" bs-form-error="$ctrl.insertNewOrganization.externalId">
             <label for="externalId">External ID (OpenID organization ID)</label>