Improve configuration

[doe300]

• [ ] remove unused/obsolete parameters
• [x] merge parameters for SIP and RTCP user-info (SDES)
• [ ] make sure, all configuration modes support all new configuration (where necessary)
• [ ] allow interactive/library configuration to start SIP configuration? (pre-set already configured parameters)??
• [ ] allow AudioHandlers/-Processors, NetworkWrappers and CryptoSuits to add new configuration options (e.g. with option-type including name, type, default value, description, category). Automatically add these options to the configuration-method used (e.g. as command-line parameter or dynamically create input fields sorted by categories)