CodeGenCactus.m: Move vectoriseExpression into new Vectorisation.m package
Move several vectorisation functions to Vectorisation.m
CalculationFunction.m: Extract new localsToGridFunctions function
CalculationFunction.m: Refactor localsToGridFunctions
Move vectorised LocalsToGridFunctions into Vectorisation.m
CalculationFunction.m: Remove Fortran from assignVariableFromExpression
CalculationFunction.m: Remove Fortran from generateCodeFromExpression
CalculationFunction.m: Remove unneeded temporary variable
CalculationFunction.m: Refactor variable assignment code (improves line breaking)
CalculationFunction.m: Move vectorisation code from simpleEquationLoop to Vectorisation.m
CalculationFunction.m: Move vectorisation code to Vectorisation.m

This is actually OpenCL-specific but uses vectorisation.  Will be moved later.
Vectorisation.m: Make several functions private

These are no longer used externally
Vectorisation.m: Rename functions
CodeGenCactus.m: Move vectorisation for AssignVariableInLoop into Vectorisation.m
CodeGenCactus.m: Remove unused DeclareAssignVariableInloop
CodeGenCactus.m: Remove unused MaybeAssignVariableInLoop
CodeGenCactus.m: Move vec_load into Vectorisation.m
Vectorisation.m: Replace vec_load with VectorisationLoadVariable
CodeGenCactus.m: Remove unused BoundaryLoop
CodeGenCactus.m: Remove unused BoundaryWithGhostsLoop