Views no longer build new Trees, Leaves if not necessary.

Views used to just store absolute paths internally and build Trees and
Leaves as needed. Now they just store the Trees and Leaves.

src/datreant/core/collections.py

@@ -224,61 +224,49 @@ def add(self, *vegs):
             elif isinstance(veg, (list, tuple)):
                 self.add(*veg)
             elif isinstance(veg, View):
-                self.add(*veg.abspaths)
+                self.add(*list(veg))
             elif isinstance(veg, Veg):
-                outconts.append(veg.abspath)
+                outconts.append(veg)
             elif (isinstance(veg, string_types) and
                     (os.path.isdir(veg) or veg.endswith(os.sep))):
                 tre = Tree(veg)
-                outconts.append(tre.abspath)
+                outconts.append(tre)
             elif isinstance(veg, string_types):
                 tre = Leaf(veg)
-                outconts.append(tre.abspath)
+                outconts.append(tre)
             else:
                 raise TypeError("'{}' not a valid input "
                                 "for View".format(veg))
 
         self._add_members(*outconts)
 
-    def _add_members(self, *abspaths):
+    def _add_members(self, *members):
         """Add many members at once.
 
         :Arguments:
-            *abspaths*
-                list of abspaths
+            *members*
+                list of Trees and Leaves
 
         """
-        for abspath in abspaths:
-            self._add_member(abspath)
+        for member in members:
+            self._add_member(member)
 
-    def _add_member(self, abspath):
+    def _add_member(self, member):
         """Add a member to the View.
 
         :Arguments:
-            *abspath*
-                absolute path of new member
+            *member*
+                Tree or Leaf to add
 
         """
-        # check if uuid already present
-        paths = [member for member in self._state]
-
-        if abspath not in paths:
-            self._state.append(abspath)
+        if member not in self._state:
+            self._state.append(member)
 
     def _list(self):
         """Return a list of members.
 
         """
-        from .trees import Leaf, Tree
-
-        outlist = []
-        for abspath in self._state:
-            if os.path.isdir(abspath) or abspath.endswith(os.sep):
-                outlist.append(Tree(abspath))
-            else:
-                outlist.append(Leaf(abspath))
-
-        return outlist
+        return list(self._state)
 
     @property
     def names(self):