"kpm restore --quiet" hides HTTP requests/cache information

parent #577 

An interesting usage mentioned by @davidfowl  is `kpm --verbose restore --quiet`. For my implementation, in this case, `--verbose` wins and here is the reason:
If `--quiet` wins, `kpm restore` blocks without showing HTTP requests/cache information. So the user might not notice that he mistakenly specified `--verbose` and `--quiet` together because he might think that `kpm restore` is blocking for some silent operations.
If `--verbose` wins, we show a bunch of HTTP request/cache information instantly after the user hit Enter key. So the user can easily notice he specified `--verbose`. The basic idea is that we make the behavior obvious & quick enough to draw users' attention.

@Eilon , do you like the idea above? Or we can give an error saying `--verbose` and `--quiet` are mutually exclusive.

I recommend making the description a bit more generic (we might eventually have more information beyond HTTP stuff).

E.g.:
`Do not show output such as HTTP request/cache information`