Fix linter errors

app/src/components/Demo/ShowText.tsx

@@ -1,6 +1,6 @@
 import * as React from 'react'
 import { Theme, withStyles } from '@material-ui/core'
-import Key from './Key';
+import Key from './Key'
 
 interface State {
   message?: string
@@ -8,8 +8,6 @@ interface State {
   location: string
 }
 
-
-
 class Demo extends React.Component<{classes: any}, State> {
   private timer: any
   constructor(props: any) {

app/src/components/Demo/index.tsx

@@ -1,6 +1,6 @@
 import * as React from 'react'
 import ShowText from './ShowText'
-import Mouse from './Mouse';
+import Mouse from './Mouse'
 
 (window as any).demo = {}
 
@@ -11,4 +11,4 @@ export default function render(props: any) {
       <Mouse />
     </span>
   )
-}
+}