Adds json parameter for POST requests
Adds review changes
Changes check on base and json. Fails on tests.
Fixes typo in test
raise RuntimeError when a single streamed request calls *iter methods than once
rm `else` after `if` then `raise` block
add-in StreamConsumedError
using the `StreamConsumedError`
make StreamConsumedError doubly inherit
fix #2247

We have to pass urllib3 the url without the authentication information,
else it will be parsed by httplib as a netloc and included in the request line
and Host header
remove unused import
Fix a couple of issues I noticed

- Don't _ prefix json in prepare_body
- Don't initialize json to []
- Don't initialize json to {}
- Reorder parameters to PreparedRequest.prepare
- Remove extra parentheses
- Update docstring
Remove timeout from __attrs__

We do not allow the user to set the timeout value on the Session any longer so
this is extraneous
Merge pull request #2265 from sigmavirus24/session-attrs

Remove timeout from __attrs__
Merge pull request #2258 from willingc/add-json

Add json parameter
Merge pull request #2241 from tijko/master

raise RuntimeError when a single streamed request calls *iter methods th...
v2.4.2 changelog
fix documentation for utils.get_unicode_from_response() :)
requests v2.4.2
Merge pull request #2249 from t-8ch/fix_2247

fix #2247