- Do not use temporary variable in soci:use

Conference Scheduler:
- Do not attempt to send an ICS message to ourselves

Capability Negotiation Tester:
- When a call changes encryption towards DTLS or ZRTP, wait for the callback encryption change before moving on as ZRTP key negotiation might be slow in some cases

Local Conference Tester:
- Expand usage of wait_for_conference_streams to make sure that a conference is full established instead of relying on the number of the state changes of a call to a particular state

Tester:
- Update suite expected duration