Added list capability to ParameterTree

ParamterTree can now return lists as nodes in the tree, rather than
simply expanding them into indexed dicts. This is required to allow
efficient iteration over parameters in e.g. the Excalibur adapter.

odin/adapters/parameter_tree.py

@@ -7,6 +7,7 @@
 
 James Hogge, Tim Nicholls, STFC Application Engineering Group.
 """
+from platform import node
 
 
 class ParameterTreeError(Exception):
@@ -203,13 +204,20 @@ def __recursive_build_tree(self, node, path=''):
 
         # Convert list or non-callable tuple to enumerated dict ; TODO - remove this?
         if isinstance(node, list) or isinstance(node, tuple):
-            node = {str(i): node[i] for i in range(len(node))}
+            #print "BUILD 1 I AM AT ", type(node), "node", node, "path", path
+
+            return [self.__recursive_build_tree(elem, path=path) for elem in node]
+            #node = {str(i): node[i] for i in range(len(node))}
 
         # Recursively check child elements
         if isinstance(node, dict):
+            #print "BUILD 2 I AM AT ", type(node), "node", node, "path", path
             return {k: self.__recursive_build_tree(
                 v, path=path + k + '/') for k, v in node.items()}
-
+
+        #if isinstance(node, list) or isinstance(node, tuple):
+            #print "BUILD 3 I AM AT ", type(node), "node", node, "path", path
+
         return node
 
     def __recursive_populate_tree(self, node):
@@ -224,13 +232,20 @@ def __recursive_populate_tree(self, node):
         """
         # If this is a branch node recurse down the tree
         if isinstance(node, dict):
+            #print "POPULATE 1 I AM AT", type(node), "node", node
             return {k: self.__recursive_populate_tree(v) for k, v in node.items()}
 
+        if isinstance(node, list) or isinstance(node, tuple):
+            #print "POPULATE 2 I AM AT", type(node), "node", node
+            return [self.__recursive_populate_tree(item) for item in node]
+
         # If this is a leaf node, check if the leaf is a r/w tuple and substitute the
         # read element of that tuple into the node
         if isinstance(node, ParameterAccessor):
+            #print "POPULATE 3 I AM AT", type(node), "node", node
             return node.get()
 
+        #print "POPULATE 4 I AM AT", type(node), "node", node
         return node
 
     # Replaces values in data_tree with values from new_data