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
Fix bug causing named headers from showing
Remove left behind debug line
Refactor error handling during excel file loading

Was originally deeply nested if statements which made making changes to
it a little hectic so I flattened it.
Remove an 'from x import *' usage
Collect case types from modules as well as cases
Merge branch 'master' into case-importer
Group case types in select by origin
Small changes to case type selection
Fix front end code for excel field selection

Disabling case field or custom field inputs if the other one is selected
works now. It doesn't make sense to be able to put content in both of
them.

Also made the forced formatting of input to acceptable field name happen
in real time instead of on change event firing.
Remove unused code and cleanup error message
Merge branch 'master' into case-importer
Rework first two screens of excel importer
Shrink the previously giant buttons
Reorder fields
Restore case type category text lost in merge