I am trying to configure the CKEditor Image Browser plugin,
firstly where do I add this?
Enable the plugin by adding it to extraPlugins and specify the imageBrowser_listUrl parameter:
CKEDITOR.replace('textareaId', { "extraPlugins": "imagebrowser", "imageBrowser_listUrl": "/path/to/images_list.json" });

If you mean simply adding it
If you mean simply adding it CKEditor, would be a lot easier to just add it to your package using CKBuilder. The plugin is located here in the add-ons repository. If you mean configuring it, might be a better idea to comment on the plugin's page (the second link). You'll get advice directly from the plugin's creator and it will let him know some things aren't clear.
Customer and Community Manager, CKSource
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