- added scalar time series 'timestamp' to merged pism files
Well-known reference for PETSc, out of date.
White-space changes.
Tweaking PISMNC.

This makes it a little easier to write a field with a custom set of
attributes.
Fix basal B.C. for enthalpy (port to 0.5).

Now PISM will always use the insulating Neumann B.C. for enthalpy at the
base *if* the base is temperate. We no longer follow the decision chart
in [Aschwanden et al].

Previously PISM set B.C. in the temperate base case as follows:

- insulating Neumann B.C. if a non-zero-thickness layer of basal
  temperate ice is present, and
- Dirichlet B.C. otherwise
Adds the basal enthalpy B.C. decision chart

... to the documenting comment of IceModel::enthalpyAndDrainageStep().
The TikZ code used to create it is in the comment at the end of the
file.
minor: change permissions so README.md instructions correct
- suggestion for a new front page for the User's Manual
- I'd like to get the projection / view angle of the surface speed plot similar to the logo, but haven't figured it out yet.
- Let me know if you don't like it, it can be easily undone.
pism-logo.png needed for prev commit to work. This file is from ice/UAF-misc/ice-climate-workshop/figures/; don't know if it is the preferred one.  At this point I don't like the look, but it may just be the projection issue.  Could the logo appear small on corner/side of cover or 2nd page or last page?
merge bad7226 with conflict-resolve in doc/ice_bib.bib
Merge commit 'fe5a70d' into till-hydro-dynamics