Bug 25464: Add ability to specify client IP and SIP account used in SIP2 logging

Bug 25464: Add ability to specify client IP and SIP account used in SIP2 logging

Bug 15253 originally had the ability to specify the incoming IP address used for
a given log statement via SIP, as well as the SIP2 account that was in use at the time.
This data is very helpful for debugging purposes, and should be brought back.

Test Plan:
1) Apply this patch
2) Update you SIP ConversionPattern to "[%d] [%p] %X{accountid}@%X{peeraddr}: %m %l %n"
3) Restart SIP
4) Use the SIP cli tester to make some SIP requests
5) View the SIP2 log, note the account id and client ip address show in the log!

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>