Changes in version 1.10:

In case of error in a numerical argument to a command line option, plzip
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.

The variable LIBS can now be set from configure.

Several descriptions have been improved in manual, '--help', and man page.

The texinfo category of the manual has been changed from 'Data Compression'
to 'Compression' to match that of gzip. (Reported by Alfred M. Szmidt).