When running tests on non-Linux systems, it was just assumed that GNU coreutils had been installed. This meant that the wrapper commands for date/ln on those systems always had gdate and gln installed. Rather than assume that, check to see if the GNU coreutils versions as present, and if not echo a warning.

PLATFORM is populated when running via `./configure && make` but this isn't guaranteed if an individual test is run directly, such as `regress/cmdline/tag.sh`. In such cases, PLATFORM will be empty, but we still want to use it. Since we test for non-linux values, only set PLATFORM if we're running on Linu so that the correct commands are used.

Remove comments which are no longer required.

Increase/decrease the currently active split. New dimensions persist for the tog session, irrespective of subsequent closures and new child views. suggested by and ok stsp@

If in a vertical (horizontal) split, switch to horizontal (vertical), and make new split mode persist. ok op@

ok stsp@

got_privsep_recv_imsg users don't need to bother to look whether the imsg type is GOT_IMSG_ERROR because got_privsep_recv_imsg already takes care of that and turns GOT_IMSG_ERROR into `struct got_error's automatically. ok stsp@

ok stsp@

Remove those includes which are searched for portably.

Left-over from how OpenRCS/OpenCVS do error handling. OK stsp@

GNU dd only accepts upper-case letters for the size units.

Setting this option will cause 'got tag' to sign all created tags using the SSH key, unless overridden by the -s flag. ok stsp@

Don't rely on '-r' for date as it's not consistent across linuxses. Instead, expand the variables required and use '-d'. OK thomas@

Add missing files for testing fetch.

When cherry-picking commits from main, do so in reverse order so they match more linearly with main.

ok stsp@

This functionality is better suited for gotadmin because it is technically a server-side repository operation when we consider the 'got' tool as the client-side tool. I have plans to move 'got import' into gotadmin as well. ok op@

ok stsp@