Add query_raw method

[diegocrzt]

Considering #75, what do you think of having a query_raw, almost the same as query, but after doing the request, and parsing json/xml return the raw string response from the server, but doing the validations for remark messages.

I am not sure if this is justified, I was using Overpy but really needed some transformations that requires the original response returned by OSM as base, so I ended up modifying overpy to do this.

Of course this could be improved but I wanted to know what you think about it.

[coveralls]

Coverage decreased (-16.5%) to 78.184% when pulling 77d333a on diegocrzt:raw_query_result into 8aa4baf on DinoTools:master.

[coveralls]

Coverage decreased (-16.5%) to 78.184% when pulling 77d333a on diegocrzt:raw_query_result into 8aa4baf on DinoTools:master.

[fakerms]

Will this pr be merged?

[devinmatte]

Something like this would be very helpful! I was really trying to get the json output it directly to disk and couldn't find a clean way to do it currently