* agent: added agent forwarding support with an example
* context: encode session id to hex string
* agent: ensure conn doesn't change in closure as loop iterates
* tests: use HostKeyCallback in ClientConfig
* README: noting examples in _example
* agent: documented exported names, added constants for temp file creation
Signed-off-by: Jeff Lindsay <progrium@gmail.com>
* context: working mostly tested context implementation and refactoring to go with it
* _example/ssh-publickey: updating new context based callbacks
* godocs related to public api changes for contexts
* context: converting []bytes to strings before putting into context
Signed-off-by: Jeff Lindsay <progrium@gmail.com>
