Refactoring: bash calling in its own function.

Also:
 - Fixes Travis build reg. bf13d2f.
 - Wrapper test now cleans up after itself.

test/wrapper.fish

@@ -39,6 +39,8 @@ for sdk_cmd in $test_commands
     echo ""
 end
 
+rm {sout, status, path}_{bash, fish}
+
 echo "Ran $test_count commands with 3 checks each."
 echo "$failures/$check_count checks failed."
 exit (math $failures != 0)