[Feature] Dynamics components

[jbcaillau]

Parse dynamics scalar components:

∂(x[1])(t) == ...
∂(x₁)(t) == ...
ẋ₁(t) == ...
ṙ(t) == ...

• $x\dot\_i must be generated (in addition to $x\_i$), aliasing to ∂(x[1])
• same for every labeled component (ṙ...)
• declaring componentwise declaration excludes all-at-once declaration
• still generate an efficient in place dynamics in the end (when mapping to functional)

[ocots]

@jbcaillau Can we close?

[jbcaillau]

no, still need to add dotted aliases for components

[ocots]

@jbcaillau See #251