Add matches for common time zones after timestamps, for #3

syntax/log.vim

@@ -47,7 +47,10 @@ syn match logDate '^20\d\{6}'
 syn match logDate '\(\(Mon\|Tue\|Wed\|Thu\|Fri\|Sat\|Sun\) \)\?\(Jan\|Feb\|Mar\|Apr\|May\|Jun\|Jul\|Aug\|Sep\|Oct\|Nov\|Dec\) [0-9 ]\d'
 
 " Matches 12:09:38 or 00:03:38.129Z or 01:32:12.102938 +0700
-syn match logTime '\d\{2}:\d\{2}:\d\{2}\(.\d\{2,6}\)\?\(\s\?[-+]\d\{2,4}\|Z\)\?\>'
+syn match logTime '\d\{2}:\d\{2}:\d\{2}\(.\d\{2,6}\)\?\(\s\?[-+]\d\{2,4}\|Z\)\?\>' nextgroup=logTimeZone skipwhite
+
+" Follows logTime, matches UTC or PDT 2019
+syn match logTimeZone '\(UTC\|PDT\|EDT\|GMT\|EST\|KST\)\( \d\{4}\)\?' contained
 
 
 " Entities
@@ -102,6 +105,7 @@ hi def link logString String
 
 hi def link logDate Identifier
 hi def link logTime Function
+hi def link logTimeZone Identifier
 
 hi def link logUrl Underlined
 hi def link logDomain Label