[dmd-beta] 64-bit: Congratulations, Walter. Let's release a beta

[David Simcha]

As probably the person who lobbied most heavily for 64-bit support to be 
D's next big priority, I want to congratulate Walter.  With the latest 
checkin, my dstats and std.parallelism libraries compile and pass all 
their unit tests in optimized, 64-bit builds.  Several of the bugs I was 
experiencing had the same root cause, which had to do with conversions 
from ulong to double.

I have no more outstanding 64-bit bugs waiting to be filed.  Unless 
others do, let's release a beta and confine 32-bit address space 
limitations to the ash heap of history, at least on Linux.