Code generator: keep track of the component in which a variable is computed (#546).
Code generator: keep track of the component in which a variable is computed (#546).

hsorby/libcellml,nickerso/libcellml,cellml/libcellml,MichaelClerx/libcellml,nickerso/libcellml,hsorby/libcellml,nickerso/libcellml,MichaelClerx/libcellml,cellml/libcellml,cellml/libcellml,cellml/libcellml,MichaelClerx/libcellml,hsorby/libcellml,nickerso/libcellml,hsorby/libcellml