Merge pull request #1141 from Eric-Brison/3.3-I4706

feat(clean): Delete unused form class (closes #4706)
refactor(docmanager): replace deprecated new_doc, getTdoc, - part 4 - (refs #2785)
refactor(docmanager): replace deprecated new_doc, getTdoc, - part 5 - (refs #2785)
refactor(docmanager): replace deprecated new_doc, getTdoc, - part 6 - (refs #2785)
refactor(docmanager): replace deprecated new_doc, getTdoc, - part 7 - (refs #2785)
feat(obsolete): delete Doc::viewxml() deprecated method (refs #4706)