pgsql: Add new make targets "world", "install-world" and

Log Message:
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Add new make targets "world", "install-world" and "installcheck-world" to build, install and check just about everything.
In addition to everything built installed and tested by all, install and installcheck targets, these build HTML Docs,
build and test contrib, and test PLs and ECPG.

Modified Files:
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pgsql:
GNUmakefile.in (r1.55 -> r1.56)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/GNUmakefile.in?r1=1.55&r2=1.56)
Makefile (r1.15 -> r1.16)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/Makefile?r1=1.15&r2=1.16)
pgsql/doc/src/sgml:
contrib.sgml (r1.15 -> r1.16)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/contrib.sgml?r1=1.15&r2=1.16)
installation.sgml (r1.339 -> r1.340)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/installation.sgml?r1=1.339&r2=1.340)