Notification support from Zach Beane with enhancements
documentation updates for notifications
Add very simple test for notifications

Issue #19
Add :unlisten SQL op
Insert WITH-STANDARD-IO-SYNTAX between INTERN and FORMAT.

In general, (intern (format "~a..." 'sym ...)) is incorrect because
FORMAT writes symbols according to *print-case*, which may differ from
the case of symbol names (uppercase in the customary readtable).
When *PRINT-CASE* is :DOWNCASE, lower case symbols such as |sym| get
interned.
return (values object is-new) from upsert-dao

is-new specifies whether the object was inserted (T) or updated (NIL)
Export and document cl-postgres:*unix-socket-dir*
Add support for (:count foo :distinct)
Cleaned up bulk copying API for public consumption
Lose the "format" option passed to copy from

The "text" format is used by default so we don't need to specify it. In this case, it's
better not to because the syntax for specifying options changed between versions 8.4 and
9.0.  Since the default works for our purposes here, we'll just use it and side-step
the syntax problem
Fix bulk copier documentation errors
add array operators: @> (contains) and @< (is contained by)
UNIX domain socket support for Clozure CL.

As with SBCL, this adds support for UNIX domain sockets to Clozure CL.
For Darwin-based machines (i.e. all Macs), we also explicitly add
support for the correct default UNIX socket directory.

The code that constructs the UNIX socket path has been abstracted out
too, since we use it in multiple places now.

It seems to me that INITIATE-CONNECTION is beginning to get a bit
unwieldy, and could probably benefit from restructuring, but I have
intentionally avoided that to reduce the impact of this change.
Mark release 1.19
Don't pass a string to md5:md5sum-sequence

Closes #27
Fix bad unwind-protect form in bulk-copy code

Closes #29
Extended the :update operation with a :from clause
Added FTS match :@@ operator
make table-description return columns in table order