Remove getSiteFiles function to simplify and speed up the export process#1457

sejas merged 14 commits intotrunkAutomattic/studio:trunkfrom

update/STU-536-remove-get-site-files-function-and-speed-up-exportAutomattic/studio:update/STU-536-remove-get-site-files-function-and-speed-up-exportCopy head branch name to clipboard