This makes the create button enabled for script providers based on SingleScriptProvider. When the button is pressed the SingleScriptFactory is queried to get an example script to fill the new macro with and then the file is created. This is based on the code for the Python script provider in tdf#56289. Change-Id: I11a6782e55ba775afed6b62f24ae0d11c347e529 Reviewed-on: https://gerrit.libreoffice.org/c/core/+/203283 Reviewed-by: Neil Roberts <nroberts@libreoffice.org> Tested-by: Jenkins