Content Focus within Web Browser Card

[nelsonni]

To enable #77 for WebBrowser cards, an extension to the current WebBrowser class is required in order to cause the web page currently loaded within a WebBrowser card to scroll to position that displays the specific content indicated by a hyperlink. This method should take into account scroll bounds for beginning and end of web pages (i.e. so that we don't scroll off the edge of a page).

[nelsonni]

Similar to #78, this issue was originally drafted when WebBrowser was a plain TypeScript Class, which inherited from an abstract template Card class. However, after refactoring the core to use React/Redux in #93, this issue can quickly be resolved through the use of forwardRef and ref objects being bubbled up from the AceEditor component (as described in securingsincity/react-ace#356), and using the following code to update the cursor location in editor:

editor.goToLine(3);

If this feature becomes necessary, we can begin implementing the underlying code. But for now, this is a wontfix issue.