lib/config.js :: set nano's request_defaults & requests http timeout

Default timeout to 5s
lib/config.js :: allow .couch-time.rc to set nano's request_defaults

 - https://github.com/dscape/nano#pool-size-and-open-sockets
 - https://github.com/mikeal/request#requestoptions-callback
cmd/auth.js :: pretty-print unauthorized error
lib/config.js :: allow user to pass in overrides for request_defaults
bin/couch-time-cli.js :: remove verbose switch statement
cmd/replicate.js :: added command to replicate database
README.md :: document new replicate command