BUG #13267: Some timezones in pg_timezone_names are missing in pg_timezone_abbrevs

The following bug has been logged on the website:

Bug reference:      13267
Logged by:          Berend De Schouwer
Email address:      berend.de.schouwer@gmail.com
PostgreSQL version: 9.3.6
Operating system:   Linux Fedora 21
Description:

Some timezone abbreviations are missing in Postgresql.  For example, 'CAT'
(Central African Time)

This means that, for example, "select 'Mon May 11 10:12:54 CAT 2015'::date;"
will not work.

I'm trying to confirm "A program refuses to accept valid input (as defined
in the documentation)."  8.5.3, 48.71 and 48.72 aren't clear as to why some
abbreviations are in one table, but not the other.

'CAT' does exist in the abbrev column in pg_timezone_names; but is missing
in pg_timezone_abbrevs;

There are 30 such abbreviations missing, not counting 'GMT...':

 AQTT
 CAT
 CHOST
 ChST
 CVT
 ECT
 GST
 HDT
 HOVST
 IRDT
 MIST
 NCT
 NRT
 ORAT
 QYZT
 ROTT
 SAKT
 SAMT
 SBT
 SRET
 SRT
 SST
 SYOT
 TLT
 VOST
 WEST
 WIB
 WIT
 WITA
 WSST