PDP10: Change incorrect interrupt bits defined for DMC/DMR device which conflicted with KMC/KDP device. Fixes issue #107

Also removed unreferenced defines for shared Unibus devices which get address and vectors through autoconfiguration.
PDP10: Fixed display of Unibus and Vector for RY device.
PDP11,VAX: Cleanup declared but undefined local routine.
PDP8: Add device buffer flush capability and keep track of data written state in the device buffer.  Fixes #87

Finishing the last DECtape device which was missed when this functionality was added to pdp11_dt, pdp18b_dt and pdp8_dt
in commits: 2934112a7003bd31c135197a01b36d969e9c79ba and c9e8121c16ca7af2b79f45bba4b220e1c95983ba

Cleaned up the pdp11, pdp18b and other pdp8 implementations to make backporting cleaner.
Made sure that buffer flushing happens correctly when simulation returns to the sim> prompt.
VS-BUILD: fix warning messages produced when converting VS2008 projects to VS2010 or VS2012
PDP10: Change display of CPU memory size to be in KW (1024) instead of (1000)
ETHER: Fix support on OSX so that builds will succeed when building network capable simulators and libpcap development components are not available.
ETHER: Fix support on OSX so that builds will succeed when building network capable simulators and libpcap development components are not available but TUN/TAP components are available.