If there is random stuff inside a .Bl block body before the first .It,

If there is random stuff inside a .Bl block body before the first .It,
do not throw a FATAL error and do not die, but just throw a WARNING
and move the stuff out of the .Bl block.

This bug felt completely 2008-ish; meanwhile, such bugs from the
Kristaps-doesnt-like-syntax-errors-so-lets-just-give-up--Era
are becoming rare, but this was one of the last survivors.

Thanks to bentley@ for reminding me to finally fix this.