feat: Add theme/config-point capability and docs. (#2641)

This is the initial addition of the config point settings to allow run time loading of GUI settings via "theme" files/parameters.
The intent is to add an example PR that shows when to use config point, how to configure it, write documentation for it etc.

platform/core/src/utils/StackManager.js

@@ -82,7 +82,7 @@ const StackManager = {
     return stackMap[displaySetInstanceUID];
   },
   /**
-   * Find a stack or reate one if it has not been created yet
+   * Find a stack or create one if it has not been created yet
    * @param displaySet The set of images to make the stack from
    * @return {Array} Array with image IDs
    */