Use LaTeX rendering for equations

Currently, the Decapodes docs visualize systems of multiphysics equations via those methods listed in https://github.com/AlgebraicJulia/DiagrammaticEquations.jl/issues/129 :
```quote
1. The Decapode eDSL
2. Diagrammatic syntax
3. Tabular, via PrettyTables
4. Pretty-printed via Term
```

However, release 0.2.6 of DiagrammaticEquations provides support for LaTeX rendering of equations.

So, we should use this new method where appropriate. Pedagogical examples where we show the table structure of a Decapode should not be replaced; other instances should be replaced.