fix: correctly destroy socket on close (QuorumDMS#208)

* chore: update owner references

* fix: correctly destroy socket on close

This fixes an issue where the client would never close, hanging the server and preventing shutdown

* fix: only set timeout if greater than 0

* fix: move dependency to top

* fix: notify of command that caused error

* fix: emit disconnect event on client close

fix: correct OPTS error code (QuorumDMS#190)

If an unknown option is given, the response should be 501

feat: 'disconnect' event (QuorumDMS#175)

Fixes QuorumDMS#174

fix: explicitly promisify fs methods

`promisifyAll` will throw if a method with the suffix `Async` already
exists.

Fixes: QuorumDMS#159

chore: audit fix

chore: simplify circle config

fix: find available port using hostname (QuorumDMS#155)

The passive url is passed to getNextPortFactory so in passive mode, the
opening of a listening port fail when the passive url is not the ip of
an interface on the ftp server host machine.

feat: remove pasv url resolution (QuorumDMS#153)

* fix: correctly try additional ports on EADDRINUSE

* feat: remove passive url host resoltion

See: QuorumDMS#139

* feat: require pasv url to be specified

* fix(pasv): check for set pasv url

* chore: update scripts

* fix(cli): remove undefined values

* chore: add cli to eslint verify

* chore: run eslint

* chore: update scripts

* feat: add maximum number of retries to port selection

* chore: simplify eslint config

* chore: simplify dev dependencies

* chore: generate contributors

* chore: update readme contributors

* chore: add verify step to release

BREAKING CHANGE: remove ipify.org automatic resolution of ip

fix: correct writable checks (QuorumDMS#147)

fix: correct writable checks

feat: expose a RNTO event (QuorumDMS#151)

* feat(commands): expose a RNTO event, updated a readme file

* feat(commands): fixed test for the RNTO

* chore: fixed prepush errors

* fix: turnback spaces into a README.md