* IntegrationTests: print Inf norm if mismatch is found

* update refdata burgers_sine_avmda

* update refdata burgers_sine_avdb

* update refdata burgers_sine_aventropy

* update refdata burgers_sine_avtci

* fixup constructor call

* more examples

* update output times; fixup gitignore

* utilize Sandbox to parse expressions from parfiles

* fixup ScalarEq bump initial data

* add examples folder with parfiles that are not ref tested

* specialize timestep for AV scheme

* implement 1st order fd approx for derivative of regularization term

* enable callbacks

* add prms field to ScalarEq's project struct

also add av_derivative_scheme parameter to ScalarEq project
to be used subsequentely

* simplify dispatch of rhs!

* update some ref tests

- euler_isentropic_flow
- euler_sod_shock_tube_bernstein
needed because previously we employed a timestep that was too large,
because it only used the local cell width but not the smallest grid
spacing

* add ref test for FV euler sod shock tube

* update ScalarEq so that FV version can use non-periodic bdry conditions

* implement FV method for Euler equation

- also refactor timestep to work with DG and FV elements
- also refactored fv_update_step! methods to now accept buffers for bdry
  values

* remove more Riemann solver stuff

* remove non-existent export

* evict riemannsolver.jl and broadcast_[volume,faces,bdry]!

* evict Riemann solver related stuff from SRHD

* evict Riemann solver related stuff from EulerEq

* evict Riemann solver related stuff from ScalarEq

* convert all in EulerEq

remove unrelated file

* convert all in ScalarEq

* re-enable srhd_smooth test

update srhd_smooth reftest

* evict old broadcasting methods

Add a finite volume method for ScalarEq

See merge request !75

* add reftest fv_advection_sine

* migrate all of ScalarEq to use broadcast_*_2! methods

* add isperiodic method for meshes

* fix grid spacing computation for SpectralElement

* fixup parametric types to subtype Mesh1d/2d

* make TODO error more comprehensive

* fixup cfl usage; add abstractions for min grid spacing

* enable add mesh kwarg to Evolution setup in order to enable FV evolution

* add timestep! and rhs! for FVElement

* do away with the State(...) syntax

* add docs to dg_rhs methods

* add FV stepper

* limit dg_rhs.jl methods to Meshes with SpectralElement

* add mesh kwarg to Evolution so that we can use a spearate stepper based on mesh type

* add a scheme parameter to Mesh

* add FVElement type

Refactor CFL parameter usage

See merge request !74

* fix tests

* remove an unreachable check

can't be reached, because a error would be thrown earlier
when multiplying a number with nothing

* remove cfl field from Evolution struct

* move cfl parameter from Mesh to Evolution section

also update all reftest parfiles

* remove CFL field from Mesh

* apply CFL factor in evolve loop and not inside projects

call the right interpolator for HRSC/smoother.jl

See merge request !73