Update TravisCI build to use Clang 3.7.

.travis.yml

@@ -1,15 +1,15 @@
 addons:
   apt:
     packages:
-    - clang-3.5
+    - clang-3.7
     - lib32stdc++6
     - lib32z1-dev
     - libc6-dev-i386
     - linux-libc-dev
     - g++-multilib
     - g++-4.8
     sources:
-    - llvm-toolchain-precise-3.5
+    - llvm-toolchain-precise-3.7
     - ubuntu-toolchain-r-test
 language: cpp
 sudo: false
@@ -20,15 +20,15 @@ before_script:
 script:
   - mkdir build && cd build
   - PATH="~/.local/bin:$PATH"
-  - CC=clang CXX=clang python ../configure.py --enable-optimize --sdks=episode1,tf2,l4d2,csgo,dota
+  - CC=clang-3.7 CXX=clang-3.7 python ../configure.py --enable-optimize --sdks=episode1,tf2,l4d2,csgo,dota
   - ambuild
   - cd .. && mkdir build-sh-opt && cd build-sh-opt
-  - CC=clang CXX=clang python ../configure.py --enable-optimize --enable-tests --sdks=
+  - CC=clang-3.7 CXX=clang-3.7 python ../configure.py --enable-optimize --enable-tests --sdks=
   - ambuild
   - ./core/sourcehook/test/test_sourcehook/test_sourcehook -v
   - ./core-legacy/sourcehook/test/test_sourcehook/test_sourcehook -v
   - cd .. && mkdir build-sh-debug && cd build-sh-debug
-  - CC=clang CXX=clang python ../configure.py --enable-debug --enable-tests --sdks=
+  - CC=clang-3.7 CXX=clang-3.7 python ../configure.py --enable-debug --enable-tests --sdks=
   - ambuild
   - ./core/sourcehook/test/test_sourcehook/test_sourcehook -v
   - ./core-legacy/sourcehook/test/test_sourcehook/test_sourcehook -v