+ Added remaining option classes. Now, the available options for the
  plugins are Integer, Real, Enum (list), BiInteger (two values, useful
  for configurations like resolutions), BiReal (two values, useful for
  configurations like resolution scaling).
+ Added a few comments to some files that needed some explanation.
+ The basic load process of plugins already works. There is still
  needed to validated the loaded data, but the structure of the plugins
  look like is already completed. Now the next step is to validate such
  structure and add the create/load/save option for the plugins to
  store the personalized values.