Short helper to add a 32 bit counter value to the MIB subtree.

def add_cnt_32bit(self,oid,value,label=None):
		"""Short helper to add a 32 bit counter value to the MIB subtree."""
		# Truncate integer to 32bits ma,x
		self.add_oid_entry(oid,'Counter32',int(value)%4294967296,label=label)