etherMAC*: padding too short frames instead throw a runtime error
ethernet interface: added IEtherEncap moduleinterface
EtherLLC: optimisation
MACAddress: fixed compiler warning for 32bit ubuntu systems. (by Till Steinbach)
EtherMACFullDuplex: wait IFG only between frames (by Till Steinbach)

the IEEE 802.3 spec explicitly says that IFG should be *after* frames, not before.

http://standards.ieee.org/getieee802/download/802.3-2008_section1.pdf

Section 4.2.3.2.1, full duplex operation:
        After the last bit of a transmitted frame, (that is, when transmitting
        changes from true to false), the MAC continues to defer for a proper interPacket-Gap (see 4.2.3.2.2)
And further on (4.2.3.2.2):
        This is intended to provide interpacket recovery time for other CSMA/CD
        sublayers and for the physical medium."
EtherMACFullDuplex: temp
EtherMAC: wait IFG only between frames
added module tests for EtherMAC and EtherMACFullDuplex -- TRANSLATE need