xml_func.py: _replace: Strip whitespace from the returned string

csvs.py: Added TsvReader to support TSV quirks. Added reader_class(). reader_and_header(): Use reader_class() to automatically use TsvReader instead of csv.reader for TSVs. Added is_tsv() and use it where `dialect.delimiter == '\t'` was used.

strings.py: Added extract_line_ending() and remove_line_ending(). ensure_newl(): Use new remove_line_ending(). Moved Parsing section to top since it is used by the other sections.

csvs.py: stream_info(): Set dialect.quoting = csv.QUOTE_NONE for TSVs because they usually don't quote fields. Factored dialect detecting code into new function sniff().

input.Makefile: verify: Added reverify option, which can be turned off to prevent regenerating the verify/%.out file from the DB (which can be time-consuming), and instead just diff verify/%.out with verify/%.ref

count_error_rows: Allow input to be specified as last arg(s) in addition to as stdin

exc.py: ExPercentTracker: When diplaying fraction of iters that had errors, don't duplicate the iter_text ("row", etc.) in the numerator

bin/map: Use new ExPercentTracker iter_num tracking to track distinct row #s with errors

exc.py: ExPercentTracker: Track iter_nums of Exceptions as well, to distinguish how many distinct iters had errors

Added bin/count_error_rows to count distinct rows with errors in `map` error messages