Updates CHANGELOG for #292

Provides more context.

Author: weierophinney

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 All notable changes to this project will be documented in this file, in reverse chronological order by release.
 
-## 2.9.2 - TBD
+## 2.9.2 - 2017-12-11
 
 ### Added
 
@@ -22,8 +22,11 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Fixed
 
-- [#292](https://github.com/zendframework/zend-db/pull/292) fixes the issue
-  with parameter names starting from colon.
+- [#292](https://github.com/zendframework/zend-db/pull/292) ensures that you may
+  reference bound parameter names using a leading colon (`:`) character when
+  using the PDO adapter. (The leading colon is not technically necessary, as the
+  adapter will prefix for you; however, this ensures portability with vanilla
+  PDO.)
 
 ## 2.9.1 - 2017-12-07