Add case creation to and refactor case import tool

Previously case import (from excel file) would only update existing
cases. This commit will allow it to create new cases if one does not
match.

Heavy refactoring was done to the view method to clean up the code and
provide better logging of changes. Originally the xml for the whole case
was submitted to update (which marked all fields as updated) but now we
only submit the changed fields.
Add ability to disable creation of new cases

User is asked if they would like to create new cases if one is not found
to update. Defaults to not creating new cases.
i18n in case import pages
Fix bug introduced with i18n on yes/no questions

These questions and the code that uses them should probably be rewritten
in general...
Moved the methods exctracted from the view to util
Merge branch 'case-importer' into staging2