Added logic to remove existing Household accounts. Moved OCR query.
Modified warning text on the converter page to reflect new behavior.

Fixes #753
Merge dev into feature/47-hhaccount-conversion
Merge dev into feature/47-hhaccount-conversion
Merge pull request #769 from SalesforceFoundation/feature/47-hhaccount-conversion

Added logic to remove existing Household accounts. Moved OCR query.