Outbound SIP OPTIONS messages will now include fromuser of related peer.

This behavior matches up more closely with the way invite/register/etc are handled.
This patch also modifies some adjacent code for code style compliance.  Pretty minor.

(closes issue ASTERISK-17616)
Reported by: Jeremy Kister
Patches:
     chan_sip.c-options-fromuser-fix-v1.patch uploaded by Jeremy Kister (license #6232)
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Merged revisions 342061 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 342062 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@342063 65c4cc65-6c06-0410-ace0-fbb531ad65f3