Develop fragmentation function

* Write unit tests for fragmentation function
* Write fragmentaion function using TDD
Reconfigure project into a python module

* Add setup.py
* Create eDicer module folder and __init__.py
* Create test module folder and __init__.py
* Move e_dicer.py into eDicer folder
Integrate travis CI build management

* Configure .travis.yml (python2.7 build dependency)
* Add requirements.txt (biopython dependency)