parsers: fix some signed comparison issues
(spotted by Steve Borho)
#!/bin/shhg init acd ahg init becho x > b/xecho '# should print nothing'hg add bhg stecho '# should fail'hg st b/xhg add b/xecho '# should fail'hg add b b/xhg stecho '# should arguably print nothing'hg st becho a > ahg ci -Ama aecho '# should fail'hg mv a bhg st