minor, provide yuck_version_read() and yuck_version_write()

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, allow for arbitrary junk behind the beef data in yuck_version_read()

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, take reference file into account for yuck scmver

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'cmd/scmver'

* cmd/scmver:
  minor, take reference file into account for yuck scmver
  minor, allow for arbitrary junk behind the beef data in yuck_version_read()
  minor, provide yuck_version_read() and yuck_version_write()