Update MainDb version to 1.0.30 to handle compatibility issues when upgrading from release/5.2 to release/5.3

Add setting to disable RTP volumes, because implementaitons that do not ignore RTP extension headers they do not support.

Do not do anything if a participant is added twice to a conference in a very short period of time - even before receiving the 200Ok response of the reINVITE

Fix soundcard sampling rate initialisation, fix non-usage of CallParams's Account property for sip routes.

Fix V4Mapped address sometimes advertised in SDP.

- and fix build options to compile only the requested KEMs
- add  missing ZRTP auth string descriptor

    to:
    - store conference information on the device holding the conference
    - correctly set the organizer by looking at the joining mode. If it is
      FocusOwner, the use it
    - Do not default organizer to me participant
    - Set the role of the me participant of a local conference to speaker

do not compile example plugin for iOS

liblinphone:
Correctly set minimum OS version for Apple devices to example plugin

Updated liblinphone & mediastreamer2 to fix an issue with OpenSLES on Android + prevent crash in PhoneStateListener

- Refactor account creator utility functions
- Migrate account creator random username and password generators from C to C++

Take into account bandwidth consumed by non-controlled streams (such as audio) for creating TMMBR requests for controlled streams. This should improve quality for medium bandwidth internet connections by avoiding a risk of congestion.