message: Removed freezable prop
  No need to make configurable - as long as the solution is reliable then it should be on permanently
diff: @@ -4,7 +4,7 @@ import { Crumb, State } from 'navigation';
  import { NavigationContext, AsyncStateNavigator } from 'navigation-react';
  import PopSync from './PopSync';
  import Scene from './Scene';
  -type NavigationStackProps = {stateNavigator: AsyncStateNavigator, title: (state: State, data: any) => string, freezable: boolean, crumbStyle: any, unmountStyle: any, hidesTabBar: any, sharedElement: any, renderScene: (state: State, data: any) => ReactNode};
  +type NavigationStackProps = {stateNavigator: AsyncStateNavigator, title: (state: State, data: any) => string, crumbStyle: any, unmountStyle: any, hidesTabBar: any, sharedElement: any, renderScene: (state: State, data: any) => ReactNode};
  type NavigationStackState = {stateNavigator: AsyncStateNavigator, keys: string[], rest: boolean};
  class NavigationStack extends React.Component<NavigationStackProps, NavigationStackState> {
  @@ -20,7 +20,6 @@ class NavigationStack extends React.Component<NavigationStackProps, NavigationSt
  this.onRest = this.onRest.bind(this);
  }
  static defaultProps = {
  - freezable: false,
  unmountStyle: () => null,
  crumbStyle: () => null,
  hidesTabBar: () => false,
  @@ -96,7 +95,7 @@ class NavigationStack extends React.Component<NavigationStackProps, NavigationSt
  }
  render() {
  var {keys, rest} = this.state;
  - var {stateNavigator, freezable, unmountStyle, crumbStyle, hidesTabBar, title, renderScene} = this.props;
  + var {stateNavigator, unmountStyle, crumbStyle, hidesTabBar, title, renderScene} = this.props;
  var {crumbs, nextCrumb} = stateNavigator.stateContext;
  return (
  <NVNavigationStack
  @@ -116,7 +115,7 @@ class NavigationStack extends React.Component<NavigationStackProps, NavigationSt
  key={key}
  crumb={crumb}
  sceneKey={key}
  - freezable={freezable && rest}
  + freezable={typeof React.Suspense !== 'undefined' && rest}
  unmountStyle={unmountStyle}
  crumbStyle={crumbStyle}
  hidesTabBar={hidesTabBar}
  