release: 2.10.0 readiness

- Updates branch aliases:
  - dev-master => 2.10.x-dev
  - dev-develop => 2.11.x-dev
- Updates CHANGELOG:
  - Moves notes about #173 to 2.10.0 release
  - Sets date for 2.10.0 release
  - Removes empty stub for 2.9.2 release

Author: weierophinney

CHANGELOG.md

@@ -2,29 +2,7 @@
 
 All notable changes to this project will be documented in this file, in reverse chronological order by release.
 
-## 2.10.0 - TBD
-
-### Added
-
-- Nothing.
-
-### Changed
-
-- Nothing.
-
-### Deprecated
-
-- Nothing.
-
-### Removed
-
-- Nothing.
-
-### Fixed
-
-- Nothing.
-
-## 2.9.2 - TBD
+## 2.10.0 - 2019-02-19
 
 ### Added
 

composer.json

@@ -47,8 +47,8 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "2.9.x-dev",
-            "dev-develop": "2.10.x-dev"
+            "dev-master": "2.10.x-dev",
+            "dev-develop": "2.11.x-dev"
         }
     },
     "scripts": {