Update to ssh-transport 0.4.1
Enable use of temporary ssh-agent

To avoid temporary keys being added to the system ssh-agent, use a local agent
when :temp-key is true.
Reopen connection completely on cache miss

Jsch needs the connection re-opened from the Session up or it will fail
with a "JschException: packet corrupt" exception.
Timeout bad server test faster
Updated project.clj, release notes and readme for 0.3.1
Merge branch 'release/0.3.1'
Merge tag 'script-exec-0.3.1' into develop

script-exec-0.3.1
Updated version for next release cycle