Fix new tests to be better. In particular, fix webraw test to specify a date on commit to be less brittle, and fix test-oldcgi to test fetching a subdirectory of a webdir instance.

#!/bin/sh

mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m test -d "1000000 0"
hg history
hg manifest
hg cat a
hg verify