#2340 create a container class `NodeAttributes`.

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@18055 b5f69653-2bf5-0310-8201-b0dafb8e1405
#2340 fix broken serialization build by archiving const pointers

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@18058 b5f69653-2bf5-0310-8201-b0dafb8e1405
#2130 Stop abusing sparse matrix in numerical Jacobian (It won't wash with PETSc 3.3)

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@18059 b5f69653-2bf5-0310-8201-b0dafb8e1405