Log Message:
Update gnumeric to version 1.12.23.

Pkgsrc changes:
 * Adjust PLIST.
 * Bump version number.
 * Depend on newer version of goffice0.10.

Upstream changes:

gnumeric 1.12.23:

Noteworthy news in this release:
  * Fuzzed file hardening.
  * Solver refactoring.

Special thanks to Juha Kylmänen from Oulu University Secure
Programming Group for running a large amount of fuzzing against
Gnumeric.

gnumeric 1.12.22:

Noteworthy news in this release:
  * Graph fixes and improvements.
  * Test suite improvements.
  * ODF/XLSX import and export fixes.
  * A schema for the ODF files we produce.

As part of our testing we check that the ODF, XLSX, and Gnumeric
files we produce are valid according to the relevant xml schema.
  * For Gnumeric files we provide the schema.
  * For XLSX there is an official schema which we use with a few
    fixes so Excel can read our files. (We consider the format to
    be defined by what XLSX writes.)
  * For ODS the situation is more problematic. We appear to be the
    first to release a schema for the ODS files we produce. That
    is mildly shocking -- several spreadsheets have ODS as their
    primary format, yet no-one seem to be validating the files they
    produce! There is an official schema for the format without
    extensions which is fine, except that no-one uses that format
    because there are lots of fairly basic things that cannot be
    expressed in the format without extensions.