Change log:
- - outgoing call connection timeout reduced
- - custom headers for invite messages made possible
- - customizable user-agent SIP field added
- - DTMF implemented
- - possibility to perform multiple simultaneous calls added
- - video/audio recording implemented
- - application interface changes (done more consistent, obsolete methods removed, parameters changed, renamings)
- - possibility to select camera and microphone added
- - tag added to TO SIP header field
- - customizable register expiration timeout
- - some of the deprecation warnings resolved
- - hold redone to be more flexible with different servers
- - various fixes
- - new developer manual written