* Defaulted background option to white for PNG/JPG export
* Attempt at fixing background colour on image output
* Reverted build location change
* WIP for white background
* WIP for white background
* Updating default colour, including saving of existing colour to restore appropriately
* Fix tests and move css change background outside the try block
* keep consistent with american english
* add method to change background color and test wether it has been called with the right params
* change color to original when save fails
Fixes#1422
