refactory some functions in Main/utility
remove unused file helpers.py
remove unused function getValidArgs()
change to use new-style classes
fix some pep8 problems
Merge pull request #896 from LipuFei/pep8_and_refactory

Pep8 and refactory
update readme
add python-requests into Windows build script
add python-requests into Mac build script
Merge pull request #897 from LipuFei/update_readme

Update readme