Merged revisions 60141,60143 via svnmerge from https://svn.boost.org/svn/boost/trunk
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r60141 | eric_niebler | 2010-03-04 11:11:35 +1100 (Thu, 04 Mar 2010) | 1 line
add non-const function call overloads to proto terminals, code reorg
r60143 | eric_niebler | 2010-03-04 13:47:46 +1100 (Thu, 04 Mar 2010) | 1 line
add a default constructor to proto::literal