Speed up getDependencyList by using transactional cache

  If the list of bt5 is huge same dependencies are
  calculated several types due recursivity at the
  same transaction making this method useless

product/ERP5/Tool/TemplateTool.py

@@ -42,6 +42,7 @@ from Products.CMFActivity.ActiveResult import ActiveResult
 from Products.ERP5Type.Globals import InitializeClass, DTMLFile, PersistentMapping
 from Products.ERP5Type.DiffUtils import DiffFile
 from Products.ERP5Type.Tool.BaseTool import BaseTool
+from Products.ERP5Type.Cache import transactional_cached
 from Products.ERP5Type import Permissions
 from Products.ERP5.Document.BusinessTemplate import BusinessTemplateMissingDependency
 from Acquisition import aq_base
@@ -876,6 +877,7 @@ class TemplateTool (BaseTool):
 
     security.declareProtected(Permissions.AccessContentsInformation,
                                'getDependencyList')
+    @transactional_cached(lambda self, bt: (self, bt))
     def getDependencyList(self, bt):
       """
        Return the list of missing dependencies for a business