Add changelog entries.

[ci skip]

Author: myronmarston

Changelog.md

@@ -1,6 +1,18 @@
 ### 3.0.0.rc1 Development
 [Full Changelog](http://github.com/rspec/rspec-core/compare/v3.0.0.beta2...master)
 
+Enhancements:
+
+* Add `config.default_formatter` attribute, which can be used to set a
+  formatter which will only be used if no other formatter is set
+  (e.g. via `--formatter`). (Myron Marston)
+
+Bug Fixes:
+
+* Fix `spec_helper.rb` file generated by `rspec --init` so that the
+  recommended settings correctly use the documentation formatter
+  when running one file. (Myron Marston)
+
 ### 3.0.0.beta2 / 2014-02-17
 [Full Changelog](http://github.com/rspec/rspec-core/compare/v3.0.0.beta1...v3.0.0.beta2)