Fixes #385 - filter input causes a toolbar view change.

- Entering a value into the pf-toolbar filter input
  box causes the toolbar viewConfig.viewSelected()
  handler to be invoked.  This causes the view to
  change if a filter is keyed in while in any
  other view.  This appears to happen because
  the return keypress is also interpreted as a
  click event, which triggers the ng-click handler
  for the view selection button.

Author: J Logan

src/filters/filter-fields-directive.js

@@ -62,6 +62,7 @@ angular.module('patternfly.filters').directive('pfFilterFields', function () {
 
       scope.onValueKeyPress = function (keyEvent) {
         if (keyEvent.which === 13) {
+          keyEvent.preventDefault();
           scope.addFilterFn(scope.currentField, scope.config.currentValue);
           scope.config.currentValue = undefined;
         }