Fix parallel I18N make issue on FreeBSD and extend vergen to work on non-git archives of the source

This pull request fixes an issue reported by Sergei Vyshenski about problems with parallel Make of the I18N component on FreeBSD.

In addition an extension for vergen is included, allowing to dump the complete revision state from within a proper git checkout to a file. This file can then late be used instead of querying git directly by vergen.
With this feature it is possible to create an archive of OpenXPKI and run the normal build operations - without the need of having git or the .git directory included in the archive.

From the vergen documentation:

vergen works best when called within a checked out git repository.
Where this is not possible (e. g. when working on an extracted
tarball without the .git directory) it is possible to include
the complete revision information before creation of the tarball
and archive this file inside the archive.

To do so, do the following in the same directory that contains the
.VERSION_DEFINITION file:

vergen --show-revisioninfo >.vergen_revision_state

If this file is present (and git is not found) subsequent calls to
vergen will use the cached information instead.