Mesh iterators. Thoughts.
Major refactorings towards an element-centric interface.
Adapting the assembly routines to the new integration interface.
Rewiring the assembly routines.
Fixed a testing bug in interior point
All tests pass with new interface.
Made disp_disk_compression into a test of elastic scaling.
Fixed mass matrix, and added a test for elastic, spatial and
displacement scalings that should exist for a linear elastic problem.
Broken commit: Working on SGBEM assembly.