Update install.md and CHANGELOG.md for 1.7.1

Signed-off-by: Aanand Prasad <aanand.prasad@gmail.com>

CHANGELOG.md

@@ -1,6 +1,47 @@
 Change log
 ==========
 
+1.7.1 (2016-05-04)
+-----------------
+
+Bug Fixes
+
+- Fixed a bug where the output of `docker-compose config` for v1 files
+  would be an invalid configuration file.
+
+- Fixed a bug where `docker-compose config` would not check the validity
+  of links.
+
+- Fixed an issue where `docker-compose help` would not output a list of
+  available commands and generic options as expected.
+
+- Fixed an issue where filtering by service when using `docker-compose logs`
+  would not apply for newly created services.
+
+- Fixed a bug where unchanged services would sometimes be recreated in
+  in the up phase when using Compose with Python 3.
+
+- Fixed an issue where API errors encountered during the up phase would
+  not be recognized as a failure state by Compose.
+
+- Fixed a bug where Compose would raise a NameError because of an undefined
+  exception name on non-Windows platforms.
+
+- Fixed a bug where the wrong version of `docker-py` would sometimes be
+  installed alongside Compose.
+
+- Fixed a bug where the host value output by `docker-machine config default`
+  would not be recognized as valid options by the `docker-compose`
+  command line.
+
+- Fixed an issue where Compose would sometimes exit unexpectedly  while
+  reading events broadcasted by a Swarm cluster.
+
+- Corrected a statement in the docs about the location of the `.env` file,
+  which is indeed read from the current directory, instead of in the same
+  location as the Compose file.
+
+
 1.7.0 (2016-04-13)
 ------------------