PDP10, PDP11: Fix compiler indicated invalid check.  Fixed #118
PDP11,VAX: Fixed data overrun due to lost interrupts whith idle enabled; fixed garbage got after EOF due to unnecesary interrupt.
PDP11,VAX: Minor change in pdp11_cr.c
PDP11, PDP10, AltairZ80: Fixed cases where assert() macro is called with an expression which has side effects and therefore wouldn't get executed if compiled with NDEBUG defined.
PDP11, PDP10, VAX, AltairZ80: enhanced the macro which aborts on an unexpected status from an expression with side effects to also write a message to sim_log or sim_deb if they happen to be open.
PDP10, PDP11: Fix compiler indicated invalid check.  Fixed #118
PDP11, PDP10, AltairZ80: Fixed cases where assert() macro is called with an expression which has side effects and therefore wouldn't get executed if compiled with NDEBUG defined.
PDP11, PDP10, VAX, AltairZ80: enhanced the macro which aborts on an unexpected status from an expression with side effects to also write a message to sim_log or sim_deb if they happen to be open.
Merge branch 'master' of git://github.com/simh/simh into crFIX-intack
Merge remote-tracking branch 'origin/master'
SDS: Install better fix for 2x real-time clock speed problem

Received fix from Mark Pizzolato for the problem of having 120 clock interrupts per second instead of 60. Tested for several hours and wall-clock time matches TSS monitor time.
SDS: Update README.sd for 940 enhancements
Merge git://github.com/simh/simh