Release 2.0.0 (20210821)

• Start using semantic versioning (https://semver.org/), starting at 2.0.0 to signal the backwards-incompatible change in the -v command line option to the shell utility (see below).
• -v now used to cancel effect of -q (use -V for version output).
• Pre-formatted markdown manual removed.
• Generation of markdown manual removed.

Release 20190528

• pax or cp will be used to copy the skeleton directory, rather than tar or cp.
• make check now now runs shellcheck on the shell script, and mandoc -T lint on the manuals. The tests are skipped if the needed tools are not found by configure.
• Several simplifications and cosmetic changes to the code.
• When using -d, require that the given directory exists.
• Add -S to disable the copying of the skeleton directory.

Release 20180719

• A skeleton directory (to pre-populate the temporary working
  directory with) may be specified by setting the SHELL_SKEL
  environment variable to the path of a directory. This environment
  variable is not used if the command line option -s or -d is used.
• /bin/sh is used if SHELL is empty or unset and no other shell is
  specified.

Release 20180422

• Added NEWS file.
• Added -q option for quiet operation.
• Added -v option to output version information.
• Added USR1 signal handler that will stop the temporary directory from being deleted when the shell exits (as if -k had been used from the start).
• Let the configure script figure out whether mktemp -t adds .XXXXXXXX to the end of the given template or not.
• Don't choke on directories whose name start with a dash.
• Now properly tested on FreeBSD 11.1.

Release 20180415

• Fixed GitHub issue #1, "Centos 7 several shells with the same name".
• Fixed GitHub issue #2, "Comparison null string to zero (int)"
• Added manual.
• Added -f option to force running the given command (bypasses check for valid login shell).
• Added -s option for specifying a "skeleton" directory whose contents will be (recursively) copied into the newly created temporary directory.
• Updated static list of shells on Solaris with shells from the shells(4) manual on a Solaris 11.4-beta system.
• Set HOME to the temporary directory.

First real release of the shell toolbox.