Bring contributors and history up to date.

Author: Lukasa

CONTRIBUTORS.rst

@@ -23,3 +23,5 @@ In chronological order:
 - Tetsuya Morimoto (@t2y)
 
   - Fixed a bug where large or incomplete frames were not handled correctly.
+  - Added hyper command-line tool.
+  - General code cleanups.

HISTORY.rst

@@ -4,6 +4,11 @@ Release History
 Upcoming
 --------
 
+*New Features*
+
+- There is now a `hyper` command-line client that supports making HTTP/2
+  requests directly from the command-line.
+
 *Minor Changes*
 
 - We not only remove the Connection header but all headers it refers to.