Leave todos.
Merge branch 'master' of github.com:geodynamics/aspect into compressible_perplex
Update steinberger material model to run with the new material model interface (calling also viscosity for the creation of the adiabatic conditions).
Add experimental support for compressibility in the steinberger material model.
Merge branch 'gplates_cookbook_patch' into compressible_perplex
Added functions to simulator access that return the surface pressure input parameter.
Small bugfixes in lookup class of steinberger material model.
Changed steinberger material model to new interface. Made the incompressible formulation consistent and added a compressible formulation.
Viscosity is now only called if adiabatic conditions is available. No need to check for that in function any more.
Rename some variables for clarity.
Added time statistics to the screen output file for timestep 0 (if Timing output frequency is zero), and add numbers and timing information to the nonlinear itterations.
New files instead of the old ones
Put more descriptive output with the nonlinear itteration counter and removed braces
Removed the timing information of the nonlinear iterations.
Merge branch 'master' into compressible_perplex
Added description to Timing output frequency, which explains the behavoir when the paramter is set to 0.
Enormous patch for free surface framework.

This is a squash of over 100 patches that implement the ability
to do free surface calculations in Aspect within an Arbitrary
Lagrangian Eulerian framework.
Merge pull request #40 from ian-r-rose/freesurface_squash2

Enormous patch for free surface framework.
Merge pull request #34 from MFraters/extra_statistics

Added extra timing and nonlinear information in the screen/opla output
Change the simple-compressible test to a more reasonable initial condition.