Refactor library to use igwn_auth_utils.requests

This MR refactors this library to use igwn_auth_utils.requests as the backend for all authenticated requests. The old httplib API is retained but with new deprecation warnings, and will be removed in a future release (gwdatafind-2.0.0).

Closes #6 (closed).

debian/control

@@ -11,19 +11,26 @@ Build-Depends:
  debhelper (>= 9),
  dh-python,
  python3-all,
+ python3-igwn-auth-utils (>= 0.2.0),
  python3-ligo-segments,
- python3-openssl,
+ python3-requests,
+ python3-safe-netrc,
  python3-setuptools,
  help2man,
  python3-pytest (>= 2.8.0),
+ python3-requests-mock,
 
 # -- python3-gwdatafind -------------------------------------------------------
 
 Package: python3-gwdatafind
 Architecture: all
-Depends: ${misc:Depends},
-         ${python3:Depends},
-         python3-ligo-segments,
+Depends:
+ ${misc:Depends},
+ ${python3:Depends},
+ python3-igwn-auth-utils (>= 0.2.0),
+ python3-ligo-segments,
+ python3-requests,
+ python3-safe-netrc,
 Description: GW data discovery Python 3 library
  The DataFind service allows users to query for the location of
  Gravitational-Wave Frame (GWF) files containing data from the