Memory leak issue during checking of all links

[khoivan88]

Hi Munter, sorry it took me a while to post the issue here.

As a summary, I am having issue with hyperlink give memory leak problem and not checking all links (external and internal).

This is the run just for internal links with it working fine:

...
> hyperlink -pri --root _build --canonicalroot https://mydomain.com/ --todo '_build/solvents' --todo 'fonts.gstatic' --todo 'file.myfontastic' _build/*.html | tap-spot

..!..........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................!!  

...
  
  1375 tests
  1372 passed
     3 todo

However, switching to testing all links, i got this issue and I think it stopped short of checking all links (sometimes, I saw the total test number smaller than the one reported by checking only internal links.

> hyperlink -pr --root _build --canonicalroot https://mydomain.com/ --todo '_build/solvents' --todo 'fonts.gstatic' --todo 'file.myfontastic' --todo '//' _build/*.html | tap-spot

..!.................................................................!.......!!..................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................,............................................................................................................!...............................................!.................!........................................(node:36296) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 pipe listeners added to [Request]. Use emitter.setMaxListeners() to increase limit
(Use `node --trace-warnings ...` to show where the warning was created)
.....!..........................................!.................!!  

  ! TODO load _build/solvents
// more TODO


  1676 tests
     1 skipped
  1665 passed
    11 todo

Would you mind having a look at this issue please? Thank you very much :)