Fix for SPACK-49.

- name conflict in imp.load_source caused this to fail.
- Python modules loaded by imp have unique names now.

lib/spack/spack/__init__.py

@@ -26,7 +26,7 @@
 import tempfile
 from llnl.util.filesystem import *
 
-# This lives in $prefix/lib/spac/spack/__file__
+# This lives in $prefix/lib/spack/spack/__file__
 prefix = ancestor(__file__, 4)
 
 # The spack script itself

lib/spack/spack/hooks/__init__.py

@@ -47,8 +47,11 @@
 def all_hook_modules():
     modules = []
     for name in list_modules(spack.hooks_path):
+        mod_name = __name__ + '.' + name
         path = join_path(spack.hooks_path, name) + ".py"
-        modules.append(imp.load_source('spack.hooks', path))
+        mod = imp.load_source(mod_name, path)
+        modules.append(mod)
+
     return modules