Changes in version 0.22:

In case of error in a numerical argument to a command line option, tarlz
now shows the name of the option and the range of valid values.

'--check-lib' now checks that LZ_API_VERSION and LZ_version_string match.

Tarlz now reports an error and exits with status 1 if '-o, --output' is used
with any operation other than '-z, --compress'.

The variable LIBS can now be set from configure.
