WIP: add more components

[baggepinnen]

Current problems to be resolved:

• Unclear how to attach components from Translational to components from Multibody since MTK errors when connectors of different types are used in connect.
  The example in runtest.jl tries to implement
  
  where Spring is a 2D component with Flange connectors whereas Body is a multibody component with Frame connectors.
• Currently, the World component is a hard-coded constant. This component is required for all models, and a new model-compiler pass that propagates the world component to all other components is required to run before the standard MTK passes. Some equations in multibody components refer to the world component, we need to figure out a way to defer the definition of these equations until the world component is known.

[YingboMa]

Unclear how to attach components from Translational to components from Multibody since MTK errors when connectors of different types are used in connect.

The spring and body in the example are a part of Multibody as well.

https://build.openmodelica.org/Documentation/Modelica.Mechanics.MultiBody.Forces.Spring.html
https://build.openmodelica.org/Documentation/Modelica.Mechanics.MultiBody.Parts.Body.html

Currently, the World component is a hard-coded constant. This component is required for all models, and a new model-compiler pass that propagates the world component to all other components is required to run before the standard MTK passes. Some equations in multibody components refer to the world component, we need to figure out a way to defer the definition of these equations until the world component is known.

You can define a singleton with some overloads.

[YingboMa]

remember compat

[baggepinnen]

superseded by

• First working components #8