Implement generic GapfillWrapper

[vvvieira]

A generic GapfillWrapper class should be implemented to decode inputs related with the model Syntax should amount to something like this - gpflw = GapfillWrapper(model, method, **kwargs):

• model should be of types AbstractModelObjectReader or any of the objects it can read
• method should be a string
• kwargs are any keyword arguments to be included in the method's property object

The latter implies the addition of a function converting dict -> GapfillProperties

GapfillWrapper instances must implement a run method accepting parameters to define context and a gapfill objective. This might be subject to change depending on which algorithms get implemented. At the very least, there should be an easy way to define both context coming from ReconstructionWrapper.run() calls and gapfill objectives in the form of constraints or Task objects. Alternatively, the latter part could be added to the GapfillWrapper init function.

[vvvieira]

Merged changes on dev and closed