so...we need to record the domain for an SMSBillable.
fix old SMSBillables with no domain
add test option for 'sending' sms billables
some sms logs have no ids (verifying messages)
regression test to catch issues generating SMSBillables when sending sms messages
dramatically improve performance of domain filter.
delete unused management command that accessed call_billable_for_sms
remove is_test kwarg
refactor create_billable_for_sms to be at the successful endpoint of sending all and receiving all sms messages
refactor test to use create_billable_for_sms directly
move create_billable_for_sms to end of function
change message length check depending on ascii or unicode
resolve database inconsistencies with the creation of this webuser for tests
latin instead of ascii...
Use encode instead of decode
Merge pull request #4246 from dimagi/billing-domain-filter-fix

Billing domain filter fix