Add flexibility to interoperability definition

[platipodium]

In our paper "Modular System for Shelves and Coasts (MOSSCO v1.0) – a flexible and multi-component framework for coupled coastal ocean ecosystem modelling" https://doi.org/10.5194/gmd-11-915-2018 we introduce the concept of flexibility for interoperability:

** Flexibility** means that the system itself is able to deal on the one hand with a diverse small or large constellation of coupled model components and on the other hand with different orders of magnitude of spatial and temporal resolutions; it is able to deal equally well with zero-, one-, two-, and three-dimensional representations of the coastal system. Flexibility implies the capability to also encapsulate existing legacy models to create one or more different “ecosystems” of models. This feature should allow for the seamless replacement of individual model components, which is an important procedure in the continual development of integrated systems. Flexibly in replacing components finally creates a test bed for model intercomparison studies.