Get py-pandas working plus some python package updates

Provide subversion (along with apr and apr-util)

petsc: remove no longer needed -Qunused-arguments hack

Added version 0.18.0.
Added 'bin/f2py' to ignore so that activation works.

Removed unneccessary dependencies on
- libdrm
- libpciaccess
- llvm
- mesa

Added recommended dependencies from the pandas project site.
http://pandas.pydata.org/pandas-docs/stable/install.html
- py-numexpr
- py-bottleneck

The py-bottleneck is a new package that is also in this branch.

Removed optional dependencies
- py-scipy
- py-matplotlib

While those are most likely desired to be in the same python stack as
pandas they are not required by pandas.

Added 'bin/f2py' to ignore so that activation works.

[WIP] GEOS Python extension did not compile with Python3.

Added new Cython version; old versions don't work with Python3.

+ Add a new version of cmake (3.5.1).

astyle@2.04: add new package

Upload of GDAL, kealib, openjpeg, py-tuiview package builds.

Removed redundant package py-libxml2.  Use libxml2 instead.

Merge branch 'eschnett/boost-mpi-osx' of git://github.com/eschnett/spack into eschnett-eschnett/boost-mpi-osx

minor fixes to hypre and muparser on Linux

Fix bug in restage

- Restage previously only removed the source directory from the stage.
- Now removes any other directories in stage as well.