[stresstest] Improve UTF-8 BOM testing

stresstest/read.cpp
stresstest/read.hpp
stresstest/stresstest.cpp
stresstest/write.cpp

- (read_records)
Add possible UTF-8 BOM skip when there is no UTF-8 BOM.

- (read_records)
- (write_records)
Change flags testing logic to possibly pass flags even when flags::none.
[stresstest] Add partial strict mode testing

stresstest/read.cpp

- (read_records)
Possibly open/associate in strict mode. When strict mode is enabled an
error would occur if the input (which comes from CSVwrite output) is
incorrect. Since CSVwrite output should always be correct there should
never be an error.

This isn't a complete test because the fail case isn't tested. To force
an error CSVwrite's output would have to be purposely corrupted.
Clarify empty record documentation

- Document that a whitespace-only record is considered empty, as long as
it's terminated.
[stresstest] Add whitespace testing

stresstest/stresstest.cpp
stresstest/util.cpp
stresstest/util.hpp

- Add possibility for space prepended and/or appended to a delimiter or
terminator.

- (generate_and_compare)
Add possibility for alternate terminator \r\n.

Redo the character count logic for readability.

- (RemoveTrailingSpaces)
New function to remove trailing spaces from a string.
Change record number type to uintmax_t

CSV/CSV.hpp
CSV/CSVread.cpp

- Change the record number type to uintmax_t from size_t to allow the
programmer to address a larger number of records. stdint.h now required.
Add function to change the delimiter in CSVread

CSV/CSV.hpp
CSV/CSVread.cpp
CSV/CSVwrite.cpp
stresstest/stresstest.cpp

- (CSVread::GetDelimiter)
New function to get the delimiter used by CSVread.

- (CSVread::SetDelimiter)
New function to set the delimiter used by CSVread.

- Make the delimiter persistent in CSVread.

- Make the delimiter and terminator persistent in CSVwrite.
Prior to this change the delimiter and terminator were reset in
CSVwrite::Reset() and were not persistent.

# stresstest/stresstest.cpp
- (generate_and_compare)
Add possibility for alternate delimiter as semi-colon.

Change delimiter/terminator tests to handle persistence.