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(dot)de(dot)schouwer(at)gmail(dot)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