usr.bin/gh-bc, contrib/bc: update to version 5.0.0

Merge commit 2f57ecae4b98e76e5d675563785a7e6c59c868c4

This is a new major release with a number of changes and extensions:

• Limited the number of temporary numbers and made the space for them static so that allocating more space for them cannot fail.
• Allowed integers with non-zero scale to be used with power, places, and shift operators.
• Added greatest common divisor and least common multiple to lib2.bc.
• Made bc and dc UTF-8 capable.
• Added the ability for users to have bc and dc quit on SIGINT.
• Added the ability for users to disable prompt and TTY mode by environment variables.
• Added the ability for users to redefine keywords.
• Added dc's modular exponentiation and divmod to bc.
• Added the ability to assign strings to variables and array elements and pass them to functions in bc.
• Added dc's asciify command and stream printing to bc.
• Added bitwise and, or, xor, left shift, right shift, reverse, left rotate, right rotate, and mod functions to lib2.bc.
• Added the functions s2u(x) and s2un(x,n), to lib2.bc.

MFC after: 1 week

(cherry picked from commit 44d4804d1945435745518cd09eb8ae6ab22ecef4)

vendor/bc: update to upstream version 5.0.2

(cherry picked from commit a60ef1802a36f2f2a5611564191440ea1c1e2f17)
(cherry picked from commit 662087dfd0668dee82ed20d00ced662aa3595059)

contrib/bc: remove files ommitted from the release

A number of files have been removed from the release distribution of
this bc implementation. They were mostly relevant for pre release
testing and benchmarking to identify regressions. The Markdown
sources of the man pages are only relevant for combinations of build
options not used in FreeBSD and need non-default conversion tools
(available as ports in FreeBSD).

All the omitted files can be found in the upstream git repository,
and they are fetched when building this software as a port. But they
have never been used in the FreeBSD base system.

(cherry picked from commit ea31d1a5c490193348e0b71fdda6d08a2c80a2eb)

Remove files that were checked in with wrong .gitattributes

These files will be added back in updated form, but are only relevant
for the Windows platform, anyway.

(cherry picked from commit d6c323eda215d05091f56d02a8274eb50c244a6f)

contrib/bc: merge version 5.1.0 from vendor branch

This version adds options and functions that allow to print numbers
in the open interval (-1 .. 1) with or without a leading 0 digit.

Additionally, an option has been added to prevent line wrap and
allows to print arbitrarily long results on a single line.

Merge commit '5d58a51571721190681c50d4bd3a1f45e6282d72'

(cherry picked from commit d43fa8ef534ac87a16843d45264f56cf11e0fcbc)

contrib/bc: update to version 5.1.1

Merge commit '6f49f5cdde1c62c4e5a743e895f3afe592b5c0e5'

(cherry picked from commit a30efc5ca7272e446abb71f0d72c76539f267bb6)

contrib/bc: temporarily disconnect the tests for 5.0.2

The tests that come with version 5.0.2 have been extended to cover the
line editing functions. It has been found that these tests generate
false negative results in FreeBSD, most likely due to an issue in the
pexpect functionality used.

These history tests are skipped on systems that do not have python and
py-pexpect installed (and thus are unlikely to cause CI test failures),
but in order to not cause irritating failures on systems were these
packages are in fact installed, I temporarily disconnect them.

I had planned to skip this version due to the issue with the history
tests, but some committer has asked me to go ahead since the currently
used version 5.0.0 contains a macro name that collides with a project
he is working on.

No MFC of this version is planned. A version 5.0.3 is expected to be
released soon, and that version will allow to reconnect the tests and
will be MFCed.

(cherry picked from commit f774652b0e837be415abd20935eae3466ea34a20)

Add back Windows only VCXProj files

(cherry picked from commit ded0d3d486eba766f613070de0ed12029a9a3816)

contrib/bc: re-enable tests after the import of version 5.1.0

The tests have been fixed to not write any data outside of the
temporary work directory provided by the test framework.

MFC after: 3 days

(cherry picked from commit b8d895faf47afb8f3b31055e2ec2db8d0df5db23)

Revert erroneous commit ded0d3d486eba

These files came from a prior commit to contrib/bc and seem to have
been placed in the top of the source tree by a failed git rebase.

Reported by: markj

(cherry picked from commit f902ca97bdbceccf62b4b02b0321af91ea398925)