Merge tag '0.5.6' into develop

clj-ssh-0.5.6
Updated version for next release cycle
Update README to use host-ip rather than localhost
Update to jsch.agentproxy 0.0.6
Add travis config
Disable keychain tests if no keychain available
Add instructions for running tests
Updated version, release notes and readme for 0.5.7
Merge branch 'release/0.5.7'