[lucida] need to manually specify bold/italic fonts with current fontspec

[Karl Berry]

In late-breaking news, it works for me if I leave off the .otf from the
\setmainfont call (contrary to the fontspec documentation):

\documentclass{article}
\usepackage{fontspec}
\setmainfont{LucidaBrightOT}
\begin{document}
roman \textit{italic} \textbf{bold \textit{bold-italic}}
\end{document}