Default Themes: Bump the version numbers and release dates.

The POT files for Twenty Ten and Eleven have also been updated.

Props laurelfulford, maedahbatool, mrahmadawais, pento.

Merges [43964] into trunk.

Fixes #45167.
Built from https://develop.svn.wordpress.org/trunk@44279


git-svn-id: https://core.svn.wordpress.org/trunk@44109 1a063a9b-81f0-0310-95a4-ce76da25c4cd