Update to latest pjsip version

git-svn-id: http://csipsimple.googlecode.com/svn/trunk/CSipSimple@2172 9f815046-5998-e9c0-b7e2-ac03a23edfa4
Keep rw emulation as affects also 2.2 devices

git-svn-id: http://csipsimple.googlecode.com/svn/trunk/CSipSimple@2173 9f815046-5998-e9c0-b7e2-ac03a23edfa4
Improve default setitngs for Nexus4 and for old devices

git-svn-id: http://csipsimple.googlecode.com/svn/trunk/CSipSimple@2174 9f815046-5998-e9c0-b7e2-ac03a23edfa4