Removed dependency on RIEMANN environment variable
Remove building of 2d layered SWE from build targets
Bug fix and add multi-layer eigen functions
Bug fixes for LAPACK calls and index permuting
Clean up Riemann solver
Merge remote-tracking branch 'clawpack/master' into multi-layer-2d
Add ability for either bottom or top layer to be dry

Also some refactoring occured.
Adding more valid states
Turn off malfunctioning warning
Major refactor of mutli-layer solvers

Includes additional allowed dry-state situations and the elimination of a
of the code that checks constantly what eigen and inundation methods have
been requested.
Take more direct clipping of GeoClaw rpn2
Merge pull request #67 from mandli/multi-layer-2d

Add multi-layer shallow water Riemann solvers