Create the `VectorPlusTemplate` method for all `VectorExpression` objects

[kwesiRutledge]

Create the VectorPlusTemplate following the sequencing of:

1. Checking that VectorExpression and Expression inputs are valid (with the Check() method) and that their dimensions match
2. Decomposing the vectors into []ScalarExpression using the ToScalarExpressions method
3. Compute the addition of each of the elements with the scalar expressions in the Expression input with the appropriate element in the Expression

func VectorPlusTemplate(ve VectorExpression, expression Expression) Expression