Backpatch addition of .git-blame-ignore-revs

This makes it more convenient for git config to contain the
blame.ignoreRevsFile setting; otherwise current git versions complain if
the file is not present.

I constructed the file for each branch by scraping the file in branch
master for commits that appear in that branch.  Because a few additional
pgindent commits have been added to the list in master since the list
was first created, this also propagates those to branches 14 and 15
where the file already existed.  Also, some entries appear to have been
made using author-date rather than committer-date in the format string,
so some timestamps are changed.  Also remove bogus whitespace in the
suggested `git log` format string.

Backpatch to all supported branches.

Discussion: https://postgr.es/m/20220711163138.o72evdeus5f5yy5z@alvherre.pgsql

Author: alvherre

.git-blame-ignore-revs

@@ -12,7 +12,7 @@
 #
 # Add new entries by adding the output of the following to the top of the file:
 #
-# $ git log --pretty=format:"%H # %cd %n# %s" $PGINDENTGITHASH -1 --date=iso
+# $ git log --pretty=format:"%H # %cd%n# %s" $PGINDENTGITHASH -1 --date=iso
 
 82d0ffae3219e4bc153a1306ce23013d168e04a2 # 2022-06-30 11:03:03 -0400
 # pgindent run prior to branching v15.
@@ -47,7 +47,7 @@ fa27dd40d5c5f56a1ee837a75c97549e992e32a4 # 2020-05-16 11:54:51 -0400
 e02ad575d8ab6b44500d2a3fd8c3212345e3aa2b # 2020-05-16 11:49:14 -0400
 # Final pgindent run with pg_bsd_indent version 2.1.
 
-5cbfce562f7cd2aab0cdc4694ce298ec3567930e # 2020-05-14 13:06:38 -0400
+5cbfce562f7cd2aab0cdc4694ce298ec3567930e # 2020-05-14 13:06:50 -0400
 # Initial pgindent and pgperltidy run for v13.
 
 b78542b9e975494bba6db2d2802439c3328d5ef7 # 2020-02-15 14:58:30 -0500
@@ -89,7 +89,7 @@ eaedf0df7197b21182f6c341a44e4fdaa3cd6ea6 # 2017-11-29 09:24:24 -0500
 382ceffdf7f620d8f2d50e451b4167d291ae2348 # 2017-06-21 15:35:54 -0400
 # Phase 3 of pgindent updates.
 
-c7b8998ebbf310a156aa38022555a24d98fdbfb4 # 2017-06-21 15:18:54 -0400
+c7b8998ebbf310a156aa38022555a24d98fdbfb4 # 2017-06-21 15:19:25 -0400
 # Phase 2 of pgindent updates.
 
 e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 # 2017-06-21 14:39:04 -0400
@@ -122,19 +122,22 @@ de94e2af184e25576b13cbda8cf825118835d1cd # 2016-04-06 11:34:02 -0400
 be060cbcd42737693f6fd425db4c139121181cce # 2016-03-09 13:51:11 -0500
 # Re-pgindent vacuumlazy.c.
 
+0231f838565d2921a0960407c4240237ba1d56ae # 2016-02-08 15:17:40 -0500
+# Re-pgindent varlena.c.
+
 d0cd7bda97a626049aa7d247374909c52399c413 # 2016-02-04 22:30:08 -0500
 # postgres_fdw: pgindent run.
 
 8d290c8ec6c182a4df1d089c21fe84c7912f01fe # 2016-01-17 19:13:18 -0500
 # Re-pgindent a few files.
 
-befa3e648ce018d84cd2a0df701927c56fe3da4e # 2015-05-24 21:44:57 -0400
+befa3e648ce018d84cd2a0df701927c56fe3da4e # 2015-05-24 21:45:01 -0400
 # Revert 9.5 pgindent changes to atomics directory files
 
 807b9e0dff663c5da875af7907a5106c0ff90673 # 2015-05-23 21:35:49 -0400
 # pgindent run for 9.5
 
-785941cdc359c6e595201ffb0df9d28f3f7173a4 # 2015-03-26 14:03:19 -0400
+785941cdc359c6e595201ffb0df9d28f3f7173a4 # 2015-03-26 14:03:25 -0400
 # Tweak __attribute__-wrapping macros for better pgindent results.
 
 7584649a1c58029a83a7a57d74cedcf1af434c97 # 2014-10-17 12:19:05 -0400