`fetchHost` doesn't follow redirects

[Petr Razumov]

I'm wondering about the decision of not following redirects with http.Client within fetchHost function: https://github.com/rverton/webanalyze/blob/master/webanalyze.go#L105

Following HTTP redirects is crucial for our use case.

What do you think about adding the ability to provide some custom http.Client to NewWebAnalyzer?

I'm going to submit a pull request to better describe the idea.

[Robin Verton]

Hi @pshevtsov,
following redirects often led to leaving the target scope/environment.

I'm open to make this more configurable if you need it.

Greetings

[Petr Razumov]

@rverton PTAL #37