This can be seen as a fix for
https://github.com/yacy/yacy_search_server/issues/343
however, the export was not flawed, it is just the impression that
something is wrong, but the export size must be smaller than the index
size because the index also containers error documents.
Now an information line is presented that shows i.e.:
"The local index currently contains 181,319 documents, only 106,887
exportable with status code 200 - the remaining are error documents."
of minutes in the past and reverted latest change. The export file dump
will now contain four data elements: f - first date of index entry write
date, l - last date of index write date, n - now-date of index dump
time, c - count of numbers inside the dump. '0N' denotes a series of
changes which will lead to the opportunity to exchange index data dumps
in a way that is needed to integrate ZeroNet index data. This will be
based on index dump sharing; that causes this commit.
