Added some info on how we can add images to the documentation

Meta/Documentation Guide.markdown

@@ -33,3 +33,18 @@ You need to have installed the program from either the GitHub page or website, t
     "documentationGuide" is the name/tag used internally by doxygen.
     "Documentation Guide" is what shows up on the output documentation.
 
+## Adding Images
+
+Use this pattern/format:
+@code
+@image html "Documentation Guide.assets/Funny-Cat-Hidden.jpg"
+@cond EXCLUDED
+![img](Documentation Guide.assets/Funny-Cat-Hidden.jpg)
+@endcond
+@endcode
+
+Which will output a single image that is both easily viewable in Doxygen, as well as Markdown viewers/editors.
+
+@cond EXCLUDED
+**Note: if you are reading this in a Markdown/text editor, do not include the '@code' and '@endcode' lines! Those are just to present it nicely for those reading in Doxygen pages. Please also switch to view the source code view if not already, that way you can see the code for the Markdown image.**
+@endcond