.travis.yml: tidy up hererocks invocation

Author: daurnimator

.travis.yml

@@ -30,11 +30,9 @@ branches:
 
 before_install:
   - pip install hererocks
-  - hererocks ~/hererocks -r^ --$LUA # Install latest LuaRocks version
-                              # plus the Lua version for this build job
-                              # into 'here' subdirectory
-  - export PATH=$PATH:~/hererocks/bin # Add directory with all installed binaries to PATH
-  - eval `luarocks path --bin`
+  - hererocks ~/hererocks -r^ --$LUA
+  - export PATH=$PATH:~/hererocks/bin
+  - eval $(luarocks path --bin)
   - luarocks install luacheck
   - luarocks install luacov-coveralls
   - luarocks install busted