Merge branch 'es/rebase-i-author-script-fix'

The "author-script" file "git rebase -i" creates got broken when we started to move the command away from shell script, which is getting fixed now. * es/rebase-i-author-script-fix: sequencer: don't die() on bogus user-edited timestamp sequencer: fix "rebase -i --root" corrupting author header timestamp sequencer: fix "rebase -i --root" corrupting author header timezone sequencer: fix "rebase -i --root" corrupting author header