Add new make targets world-bin and install-world-bin

These are the same as world and install-world respectively, but without
building or installing the documentation. There are many reasons for
wanting to be able to do this, including speed, lack of documentation
building tools, and wanting to build other formats of the documentation.
Plans for simplifying the buildfarm client code include using these
targets.

Backpatch to all live branches.

Discussion: https://postgr.es/m/6a421136-d462-b043-a8eb-e75b2861f3df@dunslane.net

GNUmakefile.in

@@ -23,6 +23,11 @@ world:
 # build src/ before contrib/
 world-contrib-recurse: world-src-recurse
 
+$(call recurse,world-bin,src config contrib,all)
+
+# build src/ before contrib/
+world-bin-contrib-recurse: world-bin-src-recurse
+
 html man:
 	$(MAKE) -C doc $@
 
@@ -39,6 +44,11 @@ install-world:
 # build src/ before contrib/
 install-world-contrib-recurse: install-world-src-recurse
 
+$(call recurse,install-world-bin,src config contrib,install)
+
+# build src/ before contrib/
+install-world-bin-contrib-recurse: install-world-bin-src-recurse
+
 $(call recurse,installdirs uninstall init-po update-po,doc src config)
 
 $(call recurse,distprep coverage,doc src config contrib)

doc/src/sgml/installation.sgml

@@ -475,6 +475,15 @@ PostgreSQL, contrib, and documentation successfully made. Ready to install.
 </screen>
   </para>
 
+  <para>
+   If you want to build everything that can be built, including the
+   additional modules (<filename>contrib</filename>), but without
+   the documentation, type instead:
+<screen>
+<userinput>make world-bin</userinput>
+</screen>
+   </para>
+
    <para>
     If you want to invoke the build from another makefile rather than
     manually, you must unset <varname>MAKELEVEL</varname> or set it to zero,
@@ -551,6 +560,12 @@ build-postgresql:
     This also installs the documentation.
    </para>
 
+   <para>
+    If you built the world without the documentation above, type instead:
+<screen>
+<userinput>make install-world-bin</userinput>
+   </para>
+
    <para>
     You can use <literal>make install-strip</literal> instead of
     <literal>make install</literal> to strip the executable files and