pgsql: Refactor format_type APIs to be more modular

Refactor format_type APIs to be more modular

Introduce a new format_type_extended, with a flags bitmask argument that
can modify the default behavior. A few compatibility and readability
wrappers remain:
format_type_be
format_type_be_qualified
format_type_with_typemod
while format_type_with_typemod_qualified, which had a single caller, is
removed.

Author: Michael Paquier, some revisions by me
Discussion: 20180213035107(dot)GA2915(at)paquier(dot)xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a26116c6cbf4117e8efaa7cfc5bacc887f01517f

Modified Files
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contrib/postgres_fdw/deparse.c | 10 +--
src/backend/utils/adt/format_type.c | 134 ++++++++++++++++++------------------
src/include/utils/builtins.h | 9 ++-
3 files changed, 81 insertions(+), 72 deletions(-)