a fix for issue 190: fix indices for gauges to respect the starting coordinates of the grid
restore the correct qinit routine for shockbubble application and update the corresponding results in verify_shockbubble_classic.txt file
Merge pull request #206 from amal-ghamdi/issue_185_fix

Issue 185 fix
fixes and modifications to advection.py

advection.py now:

* doesn't import petsc4py (this is handled by petclaw)
* returns the Controller instance claw at the end of a successful run
Merge pull request #210 from ahmadia/fix_advection2D.py

fixes and modifications to advection.py
Skips test_euler2d_shockbubble.py if no scipy

Closes #211.
Merge pull request #212 from ahmadia/fix_test_euler2d_shockbubble

Skips test_euler2d_shockbubble.py if no scipy
Added test for gauges, fixed a bug in grid.add_gauges, removed the use of solver.set_riemann_solver function and Modified parameter 'g' to be 'grav' for consistency.
Change the location
of attributes gauge_data and keep_gauges from Grid to State classes
Modifications to code for storing gauges in memory and modifications related to using the (reltol) for
the 2D psystem test
Remove all the uses of set_riemann_solver function
separating the removal of set_riemann_solver uses from other changes related to gauges
change in the error message generated when running nosetests that corresponds to the suggested
minor style modification
Merge pull request #214 from amal-ghamdi/fix_and_test_gauges

Fix and test gauges
Merge pull request #213 from amal-ghamdi/issue_184_cont

Remove all the uses of set_riemann_solver function
change from absolute to relative tolerance in testing acoustics 2D: issue #209
remove two unnecessary lines
Merge pull request #215 from amal-ghamdi/issue_209

Issue 209: replace the use of absolute error with relative error in testing homogenous acoustics 2D
add a flag to call before_step before each RK stage