Fix #140: ipfs add url wrap doesn't work

[hacdias]

ipfs.util.addFromURL now works well with the wrapWithDirectory option.

[vmx]

The change looks good. Could you please add a test case for it?

Also I'm a fan of good commit messages, so that one can find out why something was done without looking into GitHub. Some good introduction on that topic can be found at https://chris.beams.io/posts/git-commit/

[hacdias]

@vmx done! Yeah, I just didn't care much because I'd squash everything before merging and give a good description. But it's fixed now anyway.

[vmx]

The change itself looks good. But it seems that using an ipfs.io as URL makes the test time out.

[vmx]

In regards to the commit message: I normally put the "good" commit message on the first commit, even if things get squashed. This way also the commit message can be reviewed.

[hacdias]

@vmx it was probably timing out because I forgot the done() in the end. Let's see what happens now.

[vmx]

The change looks good. The CI is flaky, but it doesn't seem to be related to this change.

[hacdias]

Thanks @vmx. Ping @diasdavid