Merge pull request #1 from mauriceling/master

Setting up DOSE for installation and use as a Python module
Refactored dose as an importable module

Removed parameters dictionary and custom_functions()
Updated all functions to cater external parameters
Updated simulate() to accept external parameters
Created SIM_01.py

A complete simulation file that utilizes dose.py as a module.
Merge pull request #2 from clarencecastillo/master

Refactored dose as an importable module