Bug 9612: fix SRU response for DOM indexing

This patch makes changes to koha-conf.xml by removing the fallback section
from biblioserver and authserver. The information is in a include file on
the same server (no need to fall back) and moreover, some information
is not up-to-date and should be moved elsewhere.

The patch also simplifies the DOM retrieval-info files for auth and bib.
And eliminates superfluous F and usmarc from the dom-config files. (I felt
the urge to remove marcxml too, but left it for now; see also the second
patch.) For reference, look at the marcxml example files of Zebra.

NOTE: This patch does not deal with the Debian package installs. In the
same way koha-conf-site.xml.in, and *-retrieval-info-* could be adjusted.

Test plan:
[1] Run at least a dev install in order to copy the new files to your
    Zebra folders. Choose for DOM indexing.
    Enable the SRU server on port 9998 (small edit in koha-conf.xml).
[2] Restart Zebra and reindex -a -b -x.
[3] Verify if a search from Koha still functions as expected.
    Check the SRU output on port 9998. NOTE: If you do not pass recordSchema,
    you should get back a marc response now (instead of index schema).
    Bonus: Add your server as a Z3950 target to another Koha install. And
    perform a Z3950 search from the other server to your new install.
    Bonus: Check response from the auth and biblio socket via yaz-client.
[4] Reindex again with -a -b but without -x.
[5] Repeat Koha search, SRU response (Z3950, yaz-client).

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Bug 9612: Zconn parameters and elementSetName in _new_Zconn

This patch makes a few adjustments in C4::Context::Zconn.
It does no longer pass the (ignored) auth, syntax parameters to _new_Zconn.
Note that auth was not completely ignored in theory, but we never pass
auth=1 [while not having user/password in koha-conf].

Furthermore, it removes the elementSetName for dom indexing. Using marcxml
here does not make a difference. It only adds a constraint on what is in
the dom-config files. (It could probably be removed there now..)

Two cosmetic code changes:
Removes unused label retry.
And moved 'servername' into the database name option.

Test plan:
When using Zebra with dom indexing, do a biblio and authority search.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>