Remove transform logging

We are not using an explicit transform  anymore.
Simplify transform(): simply do average*factor

We don't need to explicit tell which transformation to use: just use the supplied
moving_average_window and scaling_factor. We can now have both transformations.
Make parameters section entirely optional

We give some defaults to it now, so the user can run a default monitor only
specifying the stream to use and it's credentials.
Modularize script and use default to parameters

We now don't demand the user to specify parameters they are optional, having
some default values.

We also have put code to parse config file into stream and monitor dictionaries
into functions, to improve code readability.
Improve documentation
Remove useless line
Put technical documentation in wiki

As stated in #32, we had too much information in this file, so we moved more
technical details to a wiki, leaving here more user related documentation.
Added Wiki reference
Link Wiki to Overview page
Added contributing section
Merge pull request #33 from cloudwalkio/simplify-config

Simplify config