Updated the TODO list.

TODO

 Core
 ~~~~
-- TOS not supported by kernel -> automatically drop routes with TOS<>0
+- Remove TOS support?
 
 - config: executable config files
-- config: define ipaddr constants?
-- config: better default protocol names
 
 - do we really need preconfig?
 
@@ -16,7 +14,6 @@ Core
 - static: check validity of route destination?
 
 - device: configuration of interface patterns
-- device: what to do if we need to shut down this protocol?
 
 - adding of route: check whether all bits not covered by masklen are zero
 
@@ -36,7 +33,7 @@ Cleanup
 - check incoming packets and log errors!!
 - check log calls for trailing newlines
 - check if all protocols set proper packet priorities and TTL's.
-- replace all NUM's by expr's
+- replace all NUM, IPA and expr tokens by constant filter expressions
 - try compiling with -Wunused
 
 Various ideas