Create procedure local symbol table

TODO

@@ -1,9 +1,4 @@
 # Name analysis
 
-- Collect all global type and procedure definitions.
-  Give errors if:
-  - The type is already defined.
-  - Base type is not defined.
-  - Replace equivalent type with its base type.
-
-- Check definitions inside procedures.
+- Ensure type, procedure, variable and parameter names are unique.
+- Check symbols used in procedures are defined.