Better blas/lapack and scipy packages: more robust, added shared variants.

- py-scipy now builds with netlib-lapack, openblas, and atlas.
- started a convention for passing lib info from blas/lapack implementations.

- Improved netlib-lapack:
  - Also build static libs when `shared` variant is enabled.
  - Enable CBLAS  build
    - needed minor patch to build correctly.

- Added `shared` variant to OpenBLAS.
  - Made OpenBLAS build properly shared and static.

var/spack/repos/builtin/packages/py-scipy/package.py

@@ -11,9 +11,15 @@ class PyScipy(Package):
 
     extends('python')
     depends_on('py-nose')
-    depends_on('py-numpy')
-    depends_on('blas')
-    depends_on('lapack')
+    depends_on('py-numpy+blas+lapack')
 
     def install(self, spec, prefix):
+        if 'atlas' in spec:
+            # libatlas.so actually isn't always installed, but this
+            # seems to make the build autodetect things correctly.
+            env['ATLAS'] = join_path(spec['atlas'].prefix.lib, 'libatlas.' + dso_suffix)
+        else:
+            env['BLAS']   = spec['blas'].blas_shared_lib
+            env['LAPACK'] = spec['lapack'].lapack_shared_lib
+
         python('setup.py', 'install', '--prefix=%s' % prefix)