Revert "Merge pull request #2831 from dimagi/revert-vellum"

This reverts commit b3345eae872e9c3c3810ac2f78757a6523a0d6f2, reversing
changes made to 5be1de723d3563157dbe9d6aa4fbc58dca80376e.
Merge branch 'master' into vellum-includes

Conflicts:
	corehq/apps/app_manager/templates/app_manager/form_designer.html
add user registration attachment xml to app.json
only ignore data in root
add auto-select model
autoselect in suite.xml
pep8
check case tag in autoselect
add raw autoselect
auto select ui
pull out a get_bind method on XForm class
add group and type information to get_questions
fix get_questions to treat repeat groups correctly as a unit

previously had an entry for the group (with a label)
followed by an entry for the repeat node (without a label)
add support for displaying question hierarchy
make readable form data hierarchical by group/repeat
make _index_on_fields a tad more explicit
update test fixture for get_questions

after which I noticed that this test actually did expose a bug
fix bug causing triggers to show as hidden nodes when include_triggers=False

recently introduced by refactor
improve formatting of readable form data

- add hovers to show raw values
- display option label rather than raw value for option questions
show unknown questions in readable form data