changed line 172 in util.py to verifier,following the argument input of function gen_varians
Merge pull request #415 from sanromd/fix_util_l172

changed argument of test_app in line 172 in util.py to verifier
Clean up comments and code in some examples.
Fix computation of cell centers with ghosts.
More cleanup of annulus advection example.
More cleanup of examples.
Remove duplicate shock bubble file.
Move import of scipy (for now) so Travis won't fail.

Also update name of shallow water 1D example file.
Use dummy values for transverse solvers if they won't be called.  Fixes #419.
Add README to examples directory.
Merge pull request #416 from ketch/clean_up_examples

Clean up examples
Merge pull request #420 from ketch/dont_require_transverse_rp

Use dummy values for transverse solvers if they won't be called.
Change aux file read error message to debug level.
Merge pull request #422 from ketch/aux_file_message

Change aux file read error message to debug level.
Update CHANGES file for 5.2.

Also add more detailed documentation of new timesteppers.
Fix #426 (writing aux with PETSc leads to empty q file).
Merge pull request #425 from ketch/update_changes

Update CHANGES file for 5.2.
PyWENO: Update weno.py to match current PyWENO release.
Merge pull request #429 from memmett/memmett-pyweno

PyWENO: Update weno.py to match current PyWENO release.
Create shocktube.py

Example script for the 3D Euler equations with dimensional splitting.
This example solves a 1D shocktube problem in a 3D domain.