tests: use killdaemons in hgweb tests
hgweb tests often failed on my system because the serve port wasn't free when a
new hgweb was started; the killed hg wasn't completely dead yet.
Now we use killdaemons which waits for the process to die.
adding a
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24