nit: the definitions of the connecting and connected state in
focus a little too much on DTLS-SRTP. Needs some wordsmithing for SCTP/data channels.
How about this?
DTLS is in the process of negotiating a secure connection and verifying the remote fingerprint. Once a secure connection is negotiated (but prior to verification of the remote fingerprint, enabled by calling start()), incoming data can flow through (and media, once DTLS/SRTP key derivation is completed).
DTLS has completed negotiation of a secure connection and verified the remote fingerprint. Outgoing data and media can now flow through.
Clarify RTCDtlsTransportState definition
Proposed fix for #294