Bug fixed.

In previous version, if path_expand get "~/hoge",
it return "/home/user/~/hoge".
Merge pull request #35 from kenbeese/bug-fixed-utility

Bug fixed.
Split error check of `manip` from execute.execute #36
Check keys in `mn`
Fix documents and refactor `run_list` > `node_list`
Merge pull request #37 from termoshtt/error_check_in_execute

Split error check of `manip` from execute.execute
Merge remote-tracking branch 'kenbeese/master' into DataProcessorServer