[boost] [mpl][doc]bug: prior.html should have Bidirectional Iterator requirement.

The prior.html document: http://www.boost.org/doc/libs/1_38_0/libs/mpl/doc/refmanual/prior.html says prior requirement is that Iterator be a Forward Iterator; yet, http://www.boost.org/doc/libs/1_38_0/libs/mpl/doc/refmanual/forward-iterator... makes no mention of prior. Also, compiling prior on a list iterator shows: /home/evansl/prog_dev/boost-svn/ro/boost-trunk/boost/mpl/next_prior.hpp:40: error: no type named 'prior' in 'struct boost::mpl::l_iter<boost::mpl::list1<char> >' Hence, the prior requirement should be Bidirectional instead of just Forward Iterator. -regards, Larry