Include startup and reload date in the CoreStatus manager message.

The CoreStartupTime and CoreReloadTime name/value pairs in the CoreStatus
response message only included the time and not the date.  This patch,
inspired by the reporter's patch, adds 2 new fields - CoreStartupDate and
CoreReloadDate - which contain the date portion of these values.

(closes issue #15000)
Reported by: sum


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@196907 65c4cc65-6c06-0410-ace0-fbb531ad65f3