Add API version to travis: 2.9.1-4,2.10
diff --git a/.travis.yml b/.travis.yml
index 4465a63..698965a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,6 +11,11 @@
     - API_VERSION=2.8.4
     - API_VERSION=2.8.5
     - API_VERSION=2.9
+    - API_VERSION=2.9.1
+    - API_VERSION=2.9.2
+    - API_VERSION=2.9.3
+    - API_VERSION=2.9.4
+    - API_VERSION=2.10
 
 install: true