Do the patching of the 'ViewElement' and 'ViewElements' attributes of 'has_traits' module in a try/except block so we don;t run into problems when TraitsGUI is not installed (the api tries to patch attributes used by traits ui, which may not work if the dependencies for traits ui are not installed).
Do the patching of the 'ViewElement' and 'ViewElements' attributes of 'has_traits' module in a try/except block so we don;t run into problems when TraitsGUI is not installed (the api tries to patch attributes used by traits ui, which may not work if the dependencies for traits ui are not installed).

burnpanck/traits,burnpanck/traits