feat: added d3 to support library, added scratch pad

src/atlasViewer/atlasViewer.constantService.service.ts

@@ -239,5 +239,6 @@ export const SUPPORT_LIBRARY_MAP : Map<string,HTMLElement> = new Map([
   ['react@16',parseURLToElement('https://unpkg.com/react@16/umd/react.development.js')],
   ['reactdom@16',parseURLToElement('https://unpkg.com/react-dom@16/umd/react-dom.development.js')],
   ['vue@2.5.16',parseURLToElement('https://cdn.jsdelivr.net/npm/vue@2.5.16/dist/vue.js')],
-  ['preact@8.4.2',parseURLToElement('https://cdn.jsdelivr.net/npm/preact@8.4.2/dist/preact.min.js')]
+  ['preact@8.4.2',parseURLToElement('https://cdn.jsdelivr.net/npm/preact@8.4.2/dist/preact.min.js')],
+  ['d3@5.7.0',parseURLToElement('https://cdnjs.cloudflare.com/ajax/libs/d3/5.7.0/d3.min.js')]
 ])

src/ui/nehubaContainer/nehubaContainer.style.css

@@ -172,3 +172,13 @@ div[mobileObliqueGuide]
   flex-direction: column;
   align-items: center;
 }
+
+div#scratch-pad
+{
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  pointer-events: none;
+}
\ No newline at end of file

src/ui/nehubaContainer/nehubaContainer.template.html

@@ -127,6 +127,10 @@
   </div>
 </layout-floating-container>
 
+<div id="scratch-pad">
+  
+</div>
+
 <mobile-overlay 
   *ngIf = "isMobile && viewerLoaded" 
   [tunableProperties] = "tunableMobileProperties"