Centralize Config Options of all dragonflow configurations

Dragonflow has many configuration options and in future there are going to be lot more. Currently all the configuration options are spread across whole code. This interface for configurations needs to be consolidated and one way of doing this is, to move the config options from their declaration in multiple modules to a few centrally managed modules. These centrally managed modules should also provide the bigger picture of the configuration.

1) As an end user I’m not affected by this change and won’t notice a difference.
2) As a developer I will find all config options in one place and will add further config options to that central place.