**Is your feature request related to a problem? Please describe.**
It's frustrating there's no option to turn off decompress. There are situations where you want to do this. Ex: having a service that collects data, but doesn't analyze it. which then passes to another service immediately/eventually.

While data is waiting or in traffic to next stop, it should stay compressed. The difference in byte size is huge (for me, 60MB vs 1-2MB). 

**Describe the solution you'd like**
Add an option to the request to not automatically decompress for me. I'm a big boy, I can handle it myself later.

**Describe alternatives you've considered**
There are none except user another lib or write own http req (which is ridiculous just to turn off a auto feature).


I can submit a PR if no one else wants to do it (it's not hard to add). But let me know how you'd like the option to be passed in? An extra options key? `axios({ url: ..., method: ..., decompress: false })` , or adding option to an existing option?


test/unit/adapters/http.js
it('should support cancel', function (done) {
    var source = axios.CancelToken.source();
    server = http.createServer(function (req, res) {
      // c
      source.cancel('Operation has been canceled.');
    }).listen(4444, function () {
      axios.get('http://localhost:4444/', {
        cancelToken: source.token
      }).catch(function (thrown) {
        assert.ok(thrown instanceof axios.Cancel, 'Promise must be rejected with a Cancel obejct');
        assert.equal(thrown.message, 'Operation has been canceled.');
        done();
      });
    });
  });
  it('should combine baseURL and url', function (done) {
    server = http.createServer(function (req, res) {
      res.end();
    }).listen(4444, function () {
      axios.get('/foo', {
        baseURL: 'http://localhost:4444/',
      }).then(function (res) {
        assert.equal(res.config.baseURL, 'http://localhost:4444/');
        assert.equal(res.config.url, '/foo');
        done();
      });
    });
  });
});