Add a simple dummy ssh test
This uses the -e flag to run a dummy script rather than actual ssh to
test the protocol over a local pipe.
#!/bin/sh
hg init
echo a > a
hg add a
hg commit -m "test" -d "0 0"
hg history
hg tag -d "0 0" "bleah"
hg history
echo foo >> .hgtags
hg tag -d "0 0" "bleah2" || echo "failed"