JDBC patch (attempt#2) for util.Serialize and jdbc2.PreparedStatement

(attempt #2) Don't use serializepatch.tgz that I sent before, use the file
attached now to this email instead.

The attached file: SerializePatch2.tgz, contains a patch for
org.postgresql.util.Serialize and org.postgresql.jdbc2.PreparedStatement that
fixes the ability to "serialize" a simple java class into a postgres table.

The current cvs seems completely broken in this support, so the patch puts it
into working condition, granted that there are many limitations with
serializing java classes into Postgres.

A little test program is included with the patches.  The comments in the
Serialize class tries to explain how all this works.

Note:
The code to do serialize appears to have been in the driver since Postgres
6.4, according to some comments in the source. My code is not adding any
totally new ability to the driver, rather just fixing what is there so that
it actually is usable. I do not think that it should affect any existing
functions of the driver that people regularly depend on.

The code is activated if you use jdbc2.PreparedStatement and try to setObject
some java class type that is unrecognized, like not String or not some other
primitive type. This will cause a sequence of function calls that results in
an instance of Serialize being instantiated for the class type passed. The
Serialize constructor will query pg_class to see if it can find an existing
table that matches the name of the java class. If found, it will continue and
try to use the table to store the object, otherwise an SQL exception is
thrown and no harm is done. Serialize.create() has to be used to setup the
table for a java class before anything can really happen with this code other
than an SQLException (unless by some freak chance a table exists that it
thinks it can use).

I saw a difference in Serialize.java between 7.1.3 and 7.2devel that I didn't
notice before, so I had to redo my changes from the 7.2devel version (why I
had to resend this patch now). I was missing the fixString stuff, which is
nice and is imporant to ensure the inserts will not fail due to embedded
single quote or unescaped backslashes. I changed that fixString function in
Serialize just a little since there is no need to muddle with escaping
newlines: only escaping single quote and literal backslashes is needed.
Postgres appears to insert newlines within strings without trouble.