sendSync: added InetSimpleModule with sendSync() implementation
sendSync: let everything subclass from InetSimpleModule
sendSync: replace send() with sendSync() everywhere except when sending to channel (PPP, EtherMAC, etc)
sendSync: hack: work around Ieee80211Mac crash (now leaks msg!)
sendSync: Ieee80211Mac: temp hack for sendSync
to review: EtherMAC,PPP: clear queue by calling clear(); TODO maybe in other MACs too???
noted a general problem with sendSync in SCTP... internal state is not
yet complete at the place of sendSync, so when we are called BACK
from another sendSync, it will find us in inconsistent state!!!
sendSyncFinally() - potential solution to previous problem?
fix to sendSyncFinally
try sendSyncFinally in SCTP -- still 1 crash. Idea: by sendSync actually doing sendSyncFinally, ALL INET TESTS should pass without change!