(maint) Update CHANGELOG for 0.4.0 release

CHANGELOG.md

@@ -1,6 +1,28 @@
+##2016-03-30 - Release 0.4.0
+
+###Summary
+
+This release adds JSON output support for strings, fixes a major bug that prevented strings from working with the 4.4.0 release of puppet, and is the last version of strings that will be released as a module.
+
+All related tickets can be found under the [PDOC][PDOC JIRA] JIRA project with the fix version of [0.4.0](https://tickets.puppetlabs.com/issues/?filter=18810).
+
+###Features
+- Support for JSON output **(PDOC-23)**
+  - Strings now has the ability to produce a JSON representation of a given puppet module
+  - The details of the JSON schema can be found [here](https://github.com/puppetlabs/puppetlabs-strings/blob/master/json_dom.md)
+  - For details on how to generate JSON, see the [README](https://github.com/puppetlabs/puppetlabs-strings/blob/master/README.md#running-puppet-strings)
+- Migrate to ruby gems as a distribution method **(PDOC-28)**
+  - This is the last release of strings that will be available as a puppet module
+  - The 0.4.0 release will be released concurrently as a ruby gem
+  - After this release, all updates will only be available via the gem
+
+###Bugfixes
+
+- Fix issue that prevented strings from running with Puppet 4.4.0 **(PDOC-75)**
+
 ##2015-09-22 - Release 0.3.1
 
-##Summary
+###Summary
 
 This is a minor bug fix release.
 
@@ -14,7 +36,7 @@ All related tickets can be found under the [PDOC][PDOC JIRA] JIRA project with t
 
 ##2015-09-21 - Release 0.3.0
 
-##Summary
+###Summary
 
 This release includes support for Puppet Types and Providers, as well as
 type checking Puppet 4x functions and defined types.
@@ -45,6 +67,7 @@ the fix version of [0.3.0](https://tickets.puppetlabs.com/issues/?filter=15529).
 
 
 ##2015-03-17 - Release 0.2.0
+
 ###Summary
 
 This release includes improvements to the HTML output generated by strings and a few bug fixes.