Add field type FT_IGNORE to generator.

This allows ignoring fields that are unnecessary or too large for an
embedded system using nanopb, while allowing them to remain in the .proto
for other platforms.

Update issue 51
Status: FixedInGit

generator/nanopb_generator.py

@@ -306,7 +306,13 @@ class Field:
 class Message:
     def __init__(self, names, desc, message_options):
         self.name = names
-        self.fields = [Field(self.name, f, get_nanopb_suboptions(f, message_options)) for f in desc.field]
+        self.fields = []
+        
+        for f in desc.field:
+            field_options = get_nanopb_suboptions(f, message_options)
+            if field_options.type != nanopb_pb2.FT_IGNORE:
+                self.fields.append(Field(self.name, f, field_options))
+        
         self.packed = message_options.packed_struct
         self.ordered_fields = self.fields[:]
         self.ordered_fields.sort()