Add options for port and base URL

This would be handy under a reverse proxy server

I cloned yesterday (12-Feb-2018), installes locally nodejs Version 9.5.0 and got this error:
bertil@debian4:~/peertransfer$ /home/bertil/local/bin/node /usr/bin/npm start

[email protected] start /home/bertil/peertransfer
[[ $NODE_EVN = production ]] && npm run prod || npm run dev

sh: 1: [[: not found

[email protected] dev /home/bertil/peertransfer
signalhub listen -p 7000 & budo --live --host localhost index.js:bundle.js -- -t envify

events.js:137
throw er; // Unhandled 'error' event
^

Error: listen EADDRINUSE :::7000
at Object._errnoException (util.js:1003:13)
at _exceptionWithHostPort (util.js:1024:20)
at Server.setupListenHandle [as _listen2] (net.js:1367:14)
at listenInCluster (net.js:1408:12)
at Server.listen (net.js:1496:7)
at listen (/home/bertil/peertransfer/node_modules/signalhub/bin.js:48:10)
at Object. (/home/bertil/peertransfer/node_modules/signalhub/bin.js:24:28)
at Module._compile (module.js:660:30)
at Object.Module._extensions..js (module.js:671:10)
at Module.load (module.js:573:32)
[0000] info Server running at http://localhost:9966/ (connect)
[0001] info LiveReload running
events.js:137
throw er; // Unhandled 'error' event
^

Error: Cannot find module 'envify' from '/home/bertil/peertransfer'
at /home/bertil/peertransfer/node_modules/resolve/lib/async.js:48:31
at processDirs (/home/bertil/peertransfer/node_modules/resolve/lib/async.js:182:39)
at ondir (/home/bertil/peertransfer/node_modules/resolve/lib/async.js:197:13)
at load (/home/bertil/peertransfer/node_modules/resolve/lib/async.js:80:43)
at onex (/home/bertil/peertransfer/node_modules/resolve/lib/async.js:105:17)
at /home/bertil/peertransfer/node_modules/resolve/lib/async.js:26:73
at FSReqWrap.oncomplete (fs.js:166:21)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] dev: signalhub listen -p 7000 & budo --live --host localhost index.js:bundle.js -- -t envify
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /home/bertil/.npm/_logs/2018-02-11T23_39_27_165Z-debug.log

npm ERR! Linux 4.9.0-4-amd64
npm ERR! argv "/home/bertil/local/bin/node" "/usr/bin/npm" "start"
npm ERR! node v9.5.0
npm ERR! npm v3.10.10
npm ERR! code ELIFECYCLE
npm ERR! [email protected] start: [[ $NODE_EVN = production ]] && npm run prod || npm run dev
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] start script '[[ $NODE_EVN = production ]] && npm run prod || npm run dev'.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the peertransfer package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! [[ $NODE_EVN = production ]] && npm run prod || npm run dev
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs peertransfer
npm ERR! Or if that isn't available, you can get their info via:
npm ERR! npm owner ls peertransfer
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR! /home/bertil/peertransfer/npm-debug.log
bertil@debian4:~/peertransfer$
Any hint to resolve this kind of problem / issue?

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