Allow Exceptions to Bubble Up for Data Translator

Remove try/except block so exceptions are raised normally. May need to
handle exceptions later.
Change Submodule Import for Error Class

Change import statement to use different syntax for submodule.
Rename Schema Attribute has_headers

Change the name of schema attribute from has_headers to has_header.
Better term, as the header is presumably a singular row in the data.
Refactor CSVParser Class

Rework all methods of CSVParser class for better encapsulation and
greater flexibility with various CSV formats.