output option is different from htttp-go to httppie

[persep]

In httppie version 0.9.8 the output option works like so:

 --output FILE, -o FILE
      Save output to FILE instead of stdout. If --download is also set, then only
      the response body is saved to FILE. Other parts of the HTTP exchange are
      printed to stderr.

But in httpie-go 0.7.0 it works like so:

-o, --output=value output file

Therefore in httppie you would use:

http https://httpbin.org/get -o test.txt

but in http-go

http-go https://httpbin.org/get -o="test.txt"

I don't know if it is intended or not but it breaks compatibility