CI file fixes

.appveyor.yml

@@ -1,7 +1,20 @@
+branches:
+    only:
+        - ci
+        - master
+skip_tags: true
 environment:
     matrix:
         - BUILD_SHARED_LIBS: ON
         - BUILD_SHARED_LIBS: OFF
+matrix:
+    fast_finish: true
 build_script:
     - cmake -DBUILD_SHARED_LIBS=%BUILD_SHARED_LIBS% .
     - cmake --build .
+notifications:
+    - provider: Email
+        to:
+            - ci@glfw.org
+    - on_build_status_failure: true
+    - on_build_status_success: false