pgsql: Improve range checks of options for pg_test_fsync and pg_test_ti

Improve range checks of options for pg_test_fsync and pg_test_timing

Both tools never had safeguard checks for the options provided, and it
was possible to make pg_test_fsync run an infinite amount of time or
pass down buggy values to pg_test_timing.

These behaviors have existed for a long time, with no actual complaints,
so no backpatch is done.  Basic TAP tests are introduced for both tools.

Author: Michael Paquier
Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/20200806062759.GE16470@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4d29e6dbd0bb6d8c3a48d0f3c7d65dc1def1b07e

Modified Files
--------------
src/bin/pg_test_fsync/.gitignore        |  2 ++
src/bin/pg_test_fsync/Makefile          |  6 ++++
src/bin/pg_test_fsync/pg_test_fsync.c   | 28 +++++++++++++++---
src/bin/pg_test_fsync/t/001_basic.pl    | 25 ++++++++++++++++
src/bin/pg_test_timing/.gitignore       |  2 ++
src/bin/pg_test_timing/Makefile         |  6 ++++
src/bin/pg_test_timing/pg_test_timing.c | 51 ++++++++++++++++++++-------------
src/bin/pg_test_timing/t/001_basic.pl   | 25 ++++++++++++++++
8 files changed, 121 insertions(+), 24 deletions(-)