Fix long-standing multimethod test error.

- New inclusive version ranges from git-fetching branch enable a fix.
- Can now write :1 to include 1.3, 1.4, etc.
  - couldn't do this before so provides() was weird.

lib/spack/spack/test/multimethod.py

@@ -73,11 +73,11 @@ def test_mpi_version(self):
 
 
     def test_undefined_mpi_version(self):
-        # This currently fails because provides() doesn't do
-        # the right thing undefined version ranges.
-        # TODO: fix this.
         pkg = spack.db.get('multimethod^mpich@0.4')
-        self.assertEqual(pkg.mpi_version(), 0)
+        self.assertEqual(pkg.mpi_version(), 1)
+
+        pkg = spack.db.get('multimethod^mpich@1.4')
+        self.assertEqual(pkg.mpi_version(), 1)
 
 
     def test_default_works(self):