Detect encoding in Response::text() (#256)

* Detect encoding and decode text response

Fixes #246

* Try to get encoding from Content-Type header

* Remove uchardet encoding detection for now

* Add non utf-8 test case for Response::text()

* Reduce copies

src/lib.rs

@@ -129,6 +129,7 @@
 //! [cookiejar_issue]: https://github.com/seanmonstar/reqwest/issues/14
 
 extern crate bytes;
+extern crate encoding_rs;
 #[macro_use]
 extern crate futures;
 extern crate hyper;