ttools: remove no-longer-required JyStilts workaround code

JyStilts had code that hacked around some inaccessible methods in
stilts.  These methods will be accessible in any version of stilts
that this version of JyStilts is likely to be working with, so
remove it.
ttools: fix broken non-table-producing JyStilts commands.

Some commands (pixfoot and tcube) do not output tables but are
instances of ConsumerTask.  The JyStilts script was incorrectly
identifying these as commands that present a table as their
primary output.  This caused both a documentation bug, and an
execution bug, since the ProcessingMode that did the work for
them was not getting invoked.  Fix the identification in JyStilts
so that only tasks which output via ChoiceMode are marked thus;
others are executed without special arrangements for making the
result available in python.
ttools: add missing getLongArrayProperty method to JELRowReader

The absence of this method meant that JEL expressions attempting to
subscript long arrays failed.  I'm 95% sure that its omission in
the first place was just an oversight rather than for some subtle
JEL reason.
table: EqualsMatchEngine now matches scalar numbers on value

The Exact match engine now considers two Number instances equal if they
have the same numeric value; so an Integer can now match a Long or a
Float etc.

Also fixed a bug which could (very rarely) cause a ClassCastException
when attempting to match array values of different types.
registry: fix namespace in SOAP RI1.0 Search request

There was an error in the SOAP request sent for RI1.0 Search operations
by the registry client.  It was generating SOAP messages that started
like this:

   <rs:Search xmlns:rs='http://www.ivoa.net/wsdl/RegistrySearch/v1.0'>
     <rs:Where xmlns:rs="http://www.ivoa.net/xml/ADQL/v1.0"
               xmlns:ad="http://www.ivoa.net/xml/ADQL/v1.0"
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
       <ad:Condition xsi:type="ad:likePredType">

The remapping of the rs prefix to the ADQL namespace is clearly wrong.
This was spotted by Menelaus Perdikeas at ESAC.

The problem was related to the fact that the Where element is generated
(by the Where2DOM class in the RAYREG package) in the ADQL namespace,
but it needs to be in the RS namespace.  I had noticed that, and
attempted to patch it up with the line:

   whereEl.setPrefix( "rs" );

Unfortunately, this does something completely different from what
I intended/hoped/assumed.

I've now rewritten it using DOM methods to generate the right starting
elements, namely:

   <rs:Search xmlns:rs="http://www.ivoa.net/wsdl/RegistrySearch/v1.0">
     <rs:Where>
       <ad:Condition xmlns:ad="http://www.ivoa.net/xml/ADQL/v1.0"
                     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                     xsi:type="ad:likePredType">

The broken code was in place for many years.  Although it worked with
the AstroGrid and Euro-VO registries, and an earlier incarnation of
the STSci/NVO/VAO registry service, it did not work after about mid-2010
with the STSci one.
registry: note regclient fix in user docs