Improved crawler logging

[Murgeye]

When using --crawl, some logging of Connection and TLS errors lacks information (i.e., the current URL or host and port) to be useful. This pull request improves the logging with this additional information.

[stamparm]

...%s" % repr(url) looks bad
...'%s'" % url looks better

[Murgeye]

I have updated the PR with the requested changes.

[stamparm]

ok. now went through changes. there is lots of noise here AFAICS. lots of redundant information with URLs. i could keep those .debug(...), but everything else seems to me will bring just noise

[Murgeye]

ok. now went through changes. there is lots of noise here AFAICS. lots of redundant information with URLs. i could keep those .debug(...), but everything else seems to me will bring just noise

I can see that this adds a lot of noise for non-crawler execution and I could put this into a second debug logging call.

However, that would mean either requiring repeating the information from the current log or (due to multithreading) risking that the error information and the URL/host:port get seperated by other logging calls in between.