improve reset(): it should fully reset instance and restore defaults

[koskokos2]

1. reset removes internal WRITE and HEADER handlers with no chance to restore behaviour set in Constructor
2. event listeners should should be restored to default state as reset implies need to reinitialise instance, so it will be more consistent

[JCMais]

Thanks!

This is a breaking change for current behavior (even if it's currently wrong), so I will include in a next major release.

Can you fix the failing test?

node-libcurl/test/curl/reset.js

Lines 68 to 71 in e299e49

	curl.on('error', function(err, curlCode) {
	//curlCode == 3 -> Invalid URL
	done(curlCode === 3 ? undefined : err);
	});

Since the event listeneres are erased, the error callback there is not going to be called the second time, so you need to add it inside the end callback again.

[koskokos2]

fixed test

[JCMais]

Thank you!