Cleanup doc strings

[clburlison]

pinpoint was a very early python project of mine and the code is in need of love.

Use Google's style guide https://google.github.io/styleguide/pyguide.html?showone=Comments#Comments

"""
This is an example of Google style.

Args:
    param1: This is the first param.
    param2: This is a second param.

Returns:
    This is a description of what is returned.

Raises:
    KeyError: Raises an exception.

"""