[master 20170126 E3] 'utils.py' (Rev. 1) (see notes)
[master 20170126 E3] 'utils.py' (Rev. 1) (see notes)

- Utility methods
- In this commit, added 2 methods to be referred to for natural filename
  sorting (i.e. sort 'a10' > 'a2' instead of 'a10' < 'a2')

KhunWasut/chempython