Disable loopy.CACHING_ENABLED

I suspect it to account for some problems!

python/dune/perftool/compile.py

@@ -5,6 +5,10 @@ Should also contain the entrypoint methods.
 """
 from __future__ import absolute_import
 
+# Disable loopy caching before we do anything else!
+import loopy
+loopy.CACHING_ENABLED = False
+
 
 def read_ufl(uflfile):
     from ufl.algorithms.formfiles import read_ufl_file, interpret_ufl_namespace