GUACAMOLE-197: Fix display issues and add translation strings for the RADIUS response field.

extensions/guacamole-auth-radius/src/main/resources/templates/radiusResponseField.html

@@ -1,5 +1 @@
-<div id="radius-challenge-text" />
-<div class="password-field">
-    <input type="{{passwordInputType}}" ng-model="model" ng-trim="false" autocorrect="off" autocapitalize="off"/>
-    <div class="icon toggle-password" ng-click="togglePassword()" title="{{getTogglePasswordHelpText() | translate}}"></div>
-</div>
+<input type="password" ng-model="model" ng-trim="false" autocorrect="off" autocapitalize="off" placeholder="{{radiusPlaceholder}}" />