apps/netutils/ntpclient:  Add a primitive NTP client.  Initial checkin is untested and probably incomplete

Back out part of  610e2aa0c224e2936fe8009ef4a2351ce607067a: Need to be able to select USB console devices when there is no /dev/console enabled.  Noted by Librae

apps/system/usbmsc:  Back out kludge that is no longer needed with the recent fix to the USB MSC class

apps/examples/igmp:  Fill out empty Kconfig file; can now be built as an NSH builtin function.  From Manuel Sthn

dhcpd_allocipaddr() should not call ntohl().  The return value is already in host order.  From Brennan Ashton

NSH cat command now adds to newline at the end of the file so that the NSH prompt is always on a newline

networking: Fix one place where the reference count was not being zeroed.  This is really a cosmetic fix UNLESS CONFIG_DEBUG_NET is enabled, then it causes assertions