Fix travis.yml

Author: smowton

.travis.yml

@@ -30,7 +30,7 @@ matrix:
             - clang-3.7
             - libubsan0
             - libc++-dev
-	    - libstdc++-5-dev
+            - libstdc++-5-dev
       before_install:
         - mkdir bin ; ln -s /usr/bin/clang-3.7 bin/gcc
       # env: COMPILER=clang++-3.7 SAN_FLAGS="-fsanitize=undefined -fno-sanitize-recover=undefined,integer -fno-omit-frame-pointer"