title: JSF components facets
body: <p>How can I find out which facets are available for a JSF component?
  For example: I know that for <strong>the &lt;h:column&gt;</strong> I can use <strong>&lt;f:facet name="header"&gt;</strong>, because I have seen it in many examples. 
  But let's say I didn't know that <strong>header</strong> facet existed for column. 
  How would I find it out? Is there some place where available facets are declared? Or is there a standard place in the documentation where facets are listed?</p>