Use introspection in several more places. Also rename AdvectionField object 'advf' rather than 'torc' for clarity.
Remove a TODO.
Compacted one of the lines to more closely match the way it was in geodynamics/master
Again, minimizing differences between this and geodyamics/master
Temperature boundary condition update

Add an update() function in temperature boundary conditions.
Call this function when time step start in core.cc
Use introspection in even more places.
Simplify a few introspection queries, remove some TODOs
Missed one
assert block layout in solver, cleanup 80f462a

Also introduce short variable names to make the code more readable. This
cleans up 80f462a.