Remove option to turn off zoom

src/app.tsx

@@ -178,7 +178,6 @@ interface Arguments {
   chartType: ChartType;
   gedcom?: string;
   images?: Map<string, string>;
-  enableZoom: boolean;
 }
 
 /**
@@ -225,7 +224,6 @@ function getArguments(location: H.Location<any>): Arguments {
 
     gedcom: location.state && location.state.data,
     images: location.state && location.state.images,
-    enableZoom: getParam('enableZoom') !== 'false', // True by default.
   };
 }
 
@@ -265,8 +263,6 @@ interface State {
   /** Source of the data. */
   source?: DataSourceEnum;
   loadingMore?: boolean;
-  /** Whether the zoom functionality is enabled. */
-  enableZoom: boolean;
 }
 
 export class App extends React.Component<RouteComponentProps, {}> {
@@ -276,7 +272,6 @@ export class App extends React.Component<RouteComponentProps, {}> {
     standalone: true,
     chartType: ChartType.Hourglass,
     showErrorPopup: false,
-    enableZoom: false,
   };
   chartRef: Chart | null = null;
 
@@ -392,7 +387,6 @@ export class App extends React.Component<RouteComponentProps, {}> {
           standalone: args.standalone,
           chartType: args.chartType,
           source: args.source,
-          enableZoom: args.enableZoom,
         }),
       );
       try {
@@ -411,7 +405,6 @@ export class App extends React.Component<RouteComponentProps, {}> {
             standalone: args.standalone,
             chartType: args.chartType,
             source: args.source,
-            enableZoom: args.enableZoom,
           }),
         );
       } catch (error) {
@@ -445,7 +438,6 @@ export class App extends React.Component<RouteComponentProps, {}> {
             standalone: args.standalone,
             chartType: args.chartType,
             source: args.source,
-            enableZoom: args.enableZoom,
             loadingMore: false,
           }),
         );
@@ -549,7 +541,6 @@ export class App extends React.Component<RouteComponentProps, {}> {
             chartType={this.state.chartType}
             onSelection={this.onSelection}
             ref={(ref) => (this.chartRef = ref)}
-            enableZoom={this.state.enableZoom}
           />
           {this.state.showSidePanel ? (
             <Responsive minWidth={768} id="sidePanel">