Fixing some output errors in Field Test CSVs

_File:
- When "Connectivity Test Failed" is in the text file, setting
_contains_Errors to True only if "Starting Test" is not in the text
file.

FieldTest_File:
- After parsing all of the tests with findAndParse__Tests(), we do a
final check for errors. If the length of our self.TestsByNum array is
not 14 (ie. there aren’t 14 test objects), and the file’s
self._contains_Errors is not set to True, then there was an unknown
error of some kind, and we set self._contains_Errors to True and the
error type/message to the appropriate values

basic_utils:
- adding the “Unknown Error” error type

FieldTest_CSVCreator:
- when the script is running, if a file caused
FieldTest_File(“FILEPATH”) to raise an error, then we want to print
that out to a file in same location the CSV will be created. This file
is named (NAME OF CSV)_errors.txt