postbio - postbio: Changes: - Modified function and index names for

Log Message:
-----------
Changes:
- Modified function and index names for int_interval to avoid conflict with
other packages;
- Added receive and send methods for int_interval type;
- stree type is now a "regular" varlena type;
- Added receive and send methods for stree type.

Modified Files:
--------------
postbio:
Makefile (r1.5 -> r1.6)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/Makefile?r1=1.5&r2=1.6)
postbio.c (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/postbio.c?r1=1.2&r2=1.3)
postbio.sql.in (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/postbio.sql.in?r1=1.4&r2=1.5)
stree.c (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/stree.c?r1=1.3&r2=1.4)

Added Files:
-----------
postbio:
intinterval.c (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/intinterval.c?rev=1.1&content-type=text/x-cvsweb-markup)

Removed Files:
-------------
postbio:
interval.c
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/postbio/postbio/interval.c)