bsdinstall: modernize the screenshots

This contains a new version of every screenshot still relevant to the
bsdinstall section of the FreeBSD handbook. They were made after booting
in EFI mode instead of the traditional BIOS mode, for a more modern look
as well as a more accurate resemblance to the actual look & feel of the
installer on current hardware.

Reviewed by:	jhb, emaste, dbaio
Sponsored by:	The FreeBSD Foundation
Pull Request:	https://github.com/freebsd/freebsd-doc/pull/303

documentation/content/en/books/handbook/bsdinstall/_index.adoc

@@ -308,7 +308,7 @@ The next section is used to toggle the available options to `On` or `Off` by pre
 The system will always boot using the settings for these options until they are modified.
 Several options can be toggled using this menu:
 
-* `ACPI Support`: If the system hangs during boot, try toggling this option to `Off`.
+* `ACPI Support`: If the system hangs during boot, try toggling this option to `Off`. This option is only present when ACPI support is available but not required.
 * `Safe Mode`: If the system still hangs during boot even with `ACPI Support` set to `Off`, try setting this option to `On`.
 * `Single User`: Toggle this option to `On` to fix an existing FreeBSD installation as described in crossref:boot[boot-singleuser,“Single-User Mode”]. Once the problem is fixed, set it back to `Off`.
 * `Verbose`: Toggle this option to `On` to see more detailed messages during the boot process. This can be useful when troubleshooting a piece of hardware.