Issue on page /Userdocs/LEMS_elements/Dynamics.html: add LEMS schema to inform users of right order

[sanjayankur31]

We require LEMS bits to follow a particular order but this information is not available to users, which means we have to infer it from errors---far from ideal. We should be able to include the schema for each lems bit like we do for NeuroML component types. That'll be useful as another tab.