pythonic access support using library for any user

[rohitdavas]

Hi,
it's a great work of your. i really appreciate.

i would like to propose the extension as functionality that allows the library to be used from python. e.g import pypoi and directly able to use the pypoi.blend(...)

for that i see the following tasks :

1. exposing the functionality.
2. documenting the function signature better that clarifies the expectations

I am putting it out if someone takes these tasks. Some functionality i have already posted in the pull request. #30
will try to implement others.

cheers,