[phobos] Status of std.gregorian

[SHOO]

I had an impression(for std.date) like yours in the past, too and made std.time.
However, there was the issue of license with Tango, and it was not
connected to Phobos.
std.gregorian was developed as a substitute, but unfortunately the API
does not even satisfy a matter.
I want something which supplements this lack heartily.


BTW, I showed the stopwatch which used a performance counter at the same time.
This was developed in the totally clean situation that did not take
influence at all of Tango.
If it is possible, I suggest that to remove std.perf(unlisted
module/NOT boost license) and combine my stopwatch module instead.