Tests to resolve doc building error.

docs/source/conf.py

@@ -248,7 +248,7 @@ latex_documents = [
 
 # The name of an image file (relative to this directory) to place at the top of
 # the title page.
-latex_logo = 'images/gprMax_logo.png'
+# latex_logo = 'images/gprMax_logo.png'
 
 # For "manual" documents, if this is true, then toplevel headings are parts,
 # not chapters.