Add -m for commit and deprecate -t
Index: hg/doc/hg.1.txt
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#!/bin/sh -x
hg init
echo a > a
hg add a
hg commit -t "test" -u test -d "0 0"
hg history
hg tag -u test -d "0 0" "bleah"
hg history
echo foo >> .hgtags
hg tag -u test -d "0 0" "bleah2" || echo "failed"