don't pass owner ids to elastic when no owner is set
use casexml submit workflow to create supply points (+ updated tests)
remove unused import
delete dead comment
update supply point products to use casexml submissions
remove other dead comment
delete unused function
add options to set username and user_id in submit_case_blocks

- also don't change the submit doc type
- update commtrack to submit as commtrack-system
revert paginator changes until we can sort out proper behavior
flip username/userid defaults
Merge pull request #637 from dimagi/cz-commtrack

convert supply point and product case creation to casexml