Allow advanced options state-related parameters to be used for TCP, UDP and ICMP

Allows the state-related parameters to be specified for UDP and ICMP as well as TCP. Discussed in forum http://forum.pfsense.org/index.php/topic,64653.0.html
The following can now be used in TCP, UDP, TCP+UDP and ICMP rules:
a) maximum state entries (max)
b) maximum number of unique source hosts (max-src-nodes)
c) maximum state entries per host (max-src-states)
firewall_rules_edit validates the allowed combinations.
filter.inc implements the allowed combinations.
I have tried various combinations with protocol TCP, TCP+UDP, UDP and ICMP. The rules come through to rules.debug and are implemented (i.e. no "errors loading the rules" messages). I presume that pf is then taking some notice of these advanced parameters in the rules.