* Replace ftdm_channel_flag_t with defines. We reached the 32bit limit where does not seem reliable
          to keep using enum.
	* Flags member for ftdm_channel_t is now uint64_t
	* Added FTDM_CHANNEL_CALL_STARTED flag to indicate when the API user knows about a call
	* Refactored raw_data member for ftdm_sigmsg_t. If raw_data needs to be freed it must be requested explicitly
          through the autofree member
	* Added collected member to ftdm_sigmsg_t for FTDM_SIGEVENT_COLLECTED data instead of using raw_data
	* Created define FTDM_DIGITS_LIMIT for DNIS/ANI digits limit
	* Fix some stat checks and outdated code in ftmod_analog
	* Refactored ftdm_channel_get_history_str API to return the time offsets and time since last state change
	* Do not send FTDM_SIGEVENT_STOP and FTDM_SIGEVENT_RELEASED on calls that were never reported to the user