Adding ColumnInformation model/migration

- All column index information (ex: street name is in column 2) will be in a seperate model
- Has_one <-> Belongs_to relationship
- Benefit: "Use these same columns for multiple datasets!"
User selected Columns working (v1)

- Users activate the clientside StepWizard and select columns
- This creates a ColumnInformation object (seperated for future features)
- The UploadedFile and ColumnInformation gets passed to the FileParser, piecing together the columns and creating TokenizedAddresses

TODO
- Test many different cases
- Slightly cryptic code (optimize later) for the build_address_string logic