Use template to generate the Dockerfile

templates/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile.template

@@ -23,10 +23,8 @@
   <%include file="../../cmake.include"/>
   <%include file="../../run_tests_addons.include"/>
   
-  # The clang-3.6 symlink for the default clang version was added
-  # to Ubuntu 16.04 recently, so make sure it's installed.
-  # Also install clang3.7.
-  RUN apt-get update && apt-get -y install clang-3.6 clang-3.7 && apt-get clean
+  # Installs clang 4.0 and 5.0, the clang++ is included in clang packages
+  RUN apt-get update && apt-get -y install clang-4.0 clang-5.0 && apt-get clean
   
   # Define the default command.
   CMD ["bash"]

tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile

@@ -82,7 +82,7 @@ RUN apt-get update && apt-get install -y cmake && apt-get clean
 RUN mkdir /var/local/jenkins
 
 
-# Installs clang 4.0 and 5.0, the clang++ is included in clang pcakges
+# Installs clang 4.0 and 5.0, the clang++ is included in clang packages
 RUN apt-get update && apt-get -y install clang-4.0 clang-5.0 && apt-get clean
 
 # Define the default command.