sort update properties to standardize diffs with dev branches
small refactor making way for updating parent cases
patch preloading to understand parent cases
add ability to update case parent
slight refactor
fix get_case_parent_xpath to accept empty string
enable once off email of custom reports
remove unused imports
requisition notifications

sorry this commit is so big. nothing ever really got unglued enough to be
able to break it up into smaller chunks. here's the summary:
- send notifications to interested parties when requisitions are updated
  so that they can take the next step in the workflow
- this is done by finding the requisition case owner and looking for
  a user with the appropriate role set for the next requisition state
- a side effect was adding owner inheritance between supply points,
  supply point products, and requisitions
- added a bunch of constants and utility functions to make things cleaner
- had to update the tests quite a bit to generate an appropriate set of
  people to notify on requisition changes
- i verified the tests by looking at the output of the sms log to console,
  still need to write something that can do better sms scripting unit
  testing a-la rapidsms
newlines
remove .gitignore in preparation for merge
remove .gitignore in preparation for merge
remove .gitignore in preparation for merge
subtree merged in core-hq (commtrack-reqs branch)
subtree merged in core-hq (email_custom_reports branch)
subtree merged in core-hq (update-parent branch)
Merge branch 'master' into core-hq-commtrack-reqs
Merge branch 'master' into core-hq-email_custom_reports
Merge branch 'master' into core-hq-update-parent
Merge branch 'master' into core-hq-email_custom_reports