Added history and release notes

HISTORY.md

@@ -0,0 +1,22 @@
+0.1.0
+=======
+
+Notes:
+------
+
+- Gem is renamed to secure_headers. This will make bundler happy. https://github.com/twitter/secureheaders/pull/26
+
+Features:
+------
+
+- ability to apply two headers, one in enforce mode, on in "experimental" mode https://github.com/twitter/secureheaders/pull/11
+- Rails 3.0 support https://github.com/twitter/secureheaders/pull/28
+
+Bug fixes, misc:
+------
+
+- Fix issue where settings in application_controller were ignored if no intializer was supplied https://github.com/twitter/secureheaders/pull/25
+- Better support for other frameworks, including docs from @achui, @bmaland
+- Rails 4 routes support from @jviney https://github.com/twitter/secureheaders/pull/13
+- data: automatically whitelisted for img-src
+- Doc updates from @ming13, @theverything, @dcollazo