MFC 281887:
Reassign copyright statements on several files from Advanced
Computing Technologies LLC to Hudson River Trading LLC.

MFC 258063,258064,258066,258097,258185,259134:
- Add an -s option to the regression tests that specifies a path to an
alternate etcupdate.sh script to test. This allows a non-installed
version of the script to be tested more easily.
- Add a pre-world mode of updating similar to the -p option that can be
passed to mergemaster.
- Fix a couple of issues with -F:
- Fix ALWAYS_INSTALL to take precedence over the FreeBSD ID checks.
- Fix the -F option in the case that the only upstream change is a
change in the FreeBSD ID and the local file is removed.
- Refresh /etc/localtime after each update using tzsetup -r.
- Regenerate /var/db/services.db when /etc/services changes.

MFC 281887:
Reassign copyright statements on several files from Advanced
Computing Technologies LLC to Hudson River Trading LLC.

MFC 258063,258064,258066,258097,258185,259134:
- Add an -s option to the regression tests that specifies a path to an
alternate etcupdate.sh script to test. This allows a non-installed
version of the script to be tested more easily.
- Add a pre-world mode of updating similar to the -p option that can be
passed to mergemaster.
- Fix a couple of issues with -F:
- Fix ALWAYS_INSTALL to take precedence over the FreeBSD ID checks.
- Fix the -F option in the case that the only upstream change is a
change in the FreeBSD ID and the local file is removed.
- Refresh /etc/localtime after each update using tzsetup -r.
- Regenerate /var/db/services.db when /etc/services changes.