Function to get current dtls retransmit timeout

[Sean Buckheister]

Hi,

what I'm missing a little is a function to query the current value of
the DTLS retransmit timer. This would be very useful for nonblocking
operations. Without such knowledge one has to poll the handshake layer
every so often, because it might want to retransmit something.
Extracting the exact value would make polling unnecessary, since one
could simply set the select() or similar timeout to that value.

Thoughts?

 -- Sean