Use tslint directly in travis CI

Author: ning-y

.travis.yml

@@ -8,5 +8,5 @@ branches:
 script:
   - yarn format:ci
   - yarn build-css
-  - yarn build-js
+  - yarn tslint -p .
   - yarn test-coveralls

src/components/assessment/__tests__/__snapshots__/AssessmentWorkspace.tsx.snap

@@ -14,7 +14,7 @@ exports[`AssessmentWorkspace page with MCQ question renders correctly 1`] = `
       <Blueprint2.Button className=\\"assessment-briefing-button\\" onClick={[Function: onClick]} text=\\"Continue\\" />
     </Blueprint2.Card>
   </Blueprint2.Dialog>
-  <Workspace controlBarProps={{...}} editorProps={{...}} editorWidth=\\"50%\\" handleEditorWidthChange={[Function: handleEditorWidthChange]} handleSideContentHeightChange={[Function: handleSideContentHeightChange]} mcq={{...}} sideContentHeight={[undefined]} sideContentProps={{...}} replProps={{...}} />
+  <Workspace controlBarProps={{...}} editorProps={[undefined]} editorWidth=\\"50%\\" handleEditorWidthChange={[Function: handleEditorWidthChange]} handleSideContentHeightChange={[Function: handleSideContentHeightChange]} mcq={{...}} sideContentHeight={[undefined]} sideContentProps={{...}} replProps={{...}} />
 </div>"
 `;