relax again wait times in tests
Implement linphone_core_accept_early_media
Fix memory leak
fix early media API and implementation
modify event API to allow adding custom headers.
It is now possible to first create the LinphoneEvent, configure it with custom headers, then send it.
Added JNI wrapper for recently added Publish/Subscribe methods + fix in previous JNI wrapper for encondig in LinphoneContent
Divide huge function in smaller blocks.
Updated ms2
Allow null String value in jni wrapper for LpConfig.setString method
Fix CMake install paths.
JNI wrapper for accept_early_media methods
Always build remote_provisioning.c for Android
JNI wrapper for LinphoneCallParams getSentVideoSize and getReceivedVideoSize methods
Fix last 2 tests failing for Android because sound card was opened twice
Update ms2
Added option to remove provisioning uri once it has been successfully applied
Simplify client certificate configuration.

We can only handle one client certificate: allow setting direct path to
the chain and key files.
Updated ms2 to fix NPE on some Android
improve SDP<->SalMediaDescription conversion and offer answer algorithm
fix crash in linphonec, update oRTP