GitLab

Add parsing a directory to get all certificates in it

- supports IPv6 DNS servers
- supports nameserver lists with both IPv4 and IPv6 servers

Added a belle_sip_dict_t that has base accessors over this storage, and the appropriate unit tests.

 - Use size_t instead of unsigned int for offset.
 - Add function to enable marshal check at runtime.
 - Enable marshal check in unit tests.

* fix many bugs and crashes:
  - rport shall not be set if not present in the request
  - received shall not be set if identical to via's host
  - belle_sip_response_get_return_hop() wasn't working without received parameter
  - belle_sip_response_get_return_hop() wasn't working if no rport and no port (that is default port to be used).

belle_sip_provider_add_authorization