travis.yml: need to unset IFS before b2 invocation.

.travis.yml

@@ -223,6 +223,7 @@ script:
     echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
   - IFS=','
   - for CXXLOCAL in $CXXSTD; do  (cd libs/config/test && ../../../b2 config_info_travis_install toolset=$TOOLSET cxxstd=$CXXLOCAL $CXXSTD_DIALECT && echo With Standard Version $CXXLOCAL && ./config_info_travis && rm ./config_info_travis)  done
+  - unset IFS
   - ./b2 -j3 libs/type_traits/test toolset=$TOOLSET cxxstd=$CXXSTD $CXXSTD_DIALECT
 
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