Introduce websocket_js_host config var.  Use it to set the host used by websocket.js .  Partial revert of a649884: keep 'host' variable name.
Actually use the host variable.  Cast to string and #inspect it so that quotes get into the JS.
Initialization of "host" variable needs to happen before websocket.js uses it.
respect secure_websocket config variable
Merge pull request #26 from Libertree/websocket-host-config

Refactor of websocket host code.