Code coverage for custom headers, including checking that cloning doesn't leak memory
Prevent quadruple-free error on shutdown
Merge pull request #688 from Metaswitch/crash_on_shutdown

[Reviewer: Andy] Prevent quadruple-free error on shutdown
Merge pull request #687 from Metaswitch/custom_header_coverage

[Reviewer: Andy] Code coverage for custom headers, including checking that cloning doesn'...
Update cpp-common
Merge pull request #692 from Metaswitch/cpp_update

[No reviewer] Update cpp-common and app-servers
Add IPv6 get converage test
Merge pull request #699 from ClearwaterCore/ipv6ut

[Reviewer Matt] - Add IPv6 HTTP get converage test
Take latest cpp-common
Merge remote-tracking branch 'origin/master' into sas_all_fixes
Fix up code coverage exclusions