This commit was manufactured by cvs2svn to create branch 'RC_1_33_0'.

svn path=/branches/RC_1_33_0/boost/boost/optional/; revision=30300
Fixed the converting assignment bug in optional<>
Fixed the usage of 'None' in converter.h, which is declared as a macro in X11/X.h

svn path=/branches/RC_1_33_0/boost/boost/optional/; revision=32531
Added simple operators << and >> to optional<>

svn path=/branches/RC_1_33_0/boost/boost/optional/; revision=32533