allow selected operator for form action conditions
allow use of 'selected' operator for form action conditions on UI
UCLA reports: Patient target dates calculations will be processed by signals now.
remove references to hqbilling in corehq
remove HQBillingAddress and HQBillingMixin
delete payments submodule
remove reference to HQBillingMixin in domain doc
truly uniquify names
report fixtures generation task fix
added removing cached reports in loop
removed unnecessary buttons from mcct paid report
Merge pull request #3638 from kkaczmarczyk/fix_paid

removed unnecessary buttons from mcct paid report
Merge pull request #3630 from dimagi/remove-hqbilling

Removes the old hqbilling (payments) submodule
Merge pull request #3632 from kkaczmarczyk/fix_fixtures

report fixtures generation task fix
Merge pull request #3635 from dimagi/accounting-test-fix

truly uniquify generated usernames
Merge pull request #3624 from dimagi/condition

allow selected operator for form action conditions
improve the way we add Instance nodes to suite xml

- pull out Instance objects as constants
- make adding <instance>s more declarative
- and guard against adding the same instance twice
rename needs_instance to require_instance

to make it not sound like it returns a boolean
Merge pull request #3640 from dimagi/inlcude-group-instance

improve the way we add Instance nodes to suite xml
auto-include instances in <entry>

include all instances that are referenced
from an xpath within the referenced <detail>s