Add 2.17.0-beta.2 to CHANGELOG

[ci skip]

(cherry picked from commit 99d993c)

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Ember Changelog
 
+### 2.17.0-beta.2 (October 17, 2017)
+- [#15613](https://github.com/emberjs/ember.js/pull/15613) [BUGFIX] Don't throw an error, when not all query params are passed to routerService.transitionTo
+- [#15707](https://github.com/emberjs/ember.js/pull/15707) [BUGFIX] Fix `canInvoke` for edge cases
+- [#15722](https://github.com/emberjs/ember.js/pull/15722) [BUGFIX] empty path in `get` helper should not throw assertion
+- [#15733](https://github.com/emberjs/ember.js/pull/15733) [BUGFIX] Fix computed sort regression when array prop initially null
+
 ### 2.17.0-beta.1 (October 9, 2017)
 
 - [#15265](https://github.com/emberjs/ember.js/pull/15265) [BUGFIX] fixed issue when passing `false` to `activeClass` for `{{link-to}}`