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

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

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b8c4261e5e8dc5c20d033970ec584991638ca041

Modified Files
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GNUmakefile.in                 | 10 ++++++++++
doc/src/sgml/installation.sgml | 15 +++++++++++++++
2 files changed, 25 insertions(+)