Resolve conflicts.
Don't fail if layered shallow water solver was not compiled.
Print error message if layered sw solver does not import.
Don't compile layered shallow water solver.
Don't compile layered shallow water solver.
Merge pull request #64 from ketch/dont_fail

Dont fail if layered shallow water solver won't compile
num_waves and num_eqn for Euler_3d.
Make 3D Euler solver work with SharpClaw.
Merge pull request #66 from ketch/euler_3d_values

Euler 3d values
Correct Roe solver; add HLL solver for Euler eqns.
Roe averages in Euler solver are computed in a separate function.
Rebase branch onto updated master.
Merge pull request #68 from hadjimy/rs_euler_eqns

Riemman solver for euler eqns
Merge remote-tracking branch 'clawpack/master' into multi-layer-2d