try to enable clang-3.5 tests

Author: waneck

.travis.yml

@@ -7,8 +7,11 @@ matrix:
         - sudo apt-get install -y clang
         - export CC=clang
         - export CXX=clang++
-    # - env: TEST_NAME="clang bleeding"
-    #   before_install:
+    - env: TEST_NAME="clang bleeding"
+      before_install:
+        - sudo apt-get install -y clang-3.5
+        - export CC=clang
+        - export CXX=clang++
     #     - sudo add-apt-repository -y ppa:xorg-edgers/ppa 
     #     - sudo apt-get update
     #     - sudo apt-get install -y clang-3.5