Czech translation files updated by Stanislav Horacek (trunk https://trac.osgeo.org/grass/changeset/68245, https://trac.osgeo.org/grass/changeset/68249)

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@68250 15284696-431f-4ddb-bdfa-cd5b030d7da7