Add changelog entry

CHANGELOG-1.0.md

@@ -3,13 +3,15 @@ CHANGELOG
 
 This changelog references the relevant changes done in minor version updates.
 
-1.0.9 (????-??-??)
+1.0.9 (2017-01-29)
 ------------------
 
 All issues and pull requests under this release may be found under the
 [1.0.9](https://github.com/alcaeus/mongo-php-adapter/issues?q=milestone%3A1.0.9)
 milestone.
 
+ * [#157](https://github.com/alcaeus/mongo-php-adapter/pull/157) fixes a regression
+ introduced in 1.0.8 when using query projection with numeric field names.
  * [#155](https://github.com/alcaeus/mongo-php-adapter/pull/155) fixes the handling
  of BSON types when converting legacy types to BSON types.
  * [#154](https://github.com/alcaeus/mongo-php-adapter/pull/154) makes the `options`