Remove generated html before generating a new version.

svn path=/trunk/libs/icl/; revision=82952
Fixed documentation flaw #7947, reported by Marvin Sielenkemper.

svn path=/trunk/libs/icl/; revision=82953
Made the data of identity_element static in order to avoid unnecessary default constructions.

svn path=/trunk/boost/icl/; revision=82956
Adaptations of some tests for gcc-4.7.1-c++11

svn path=/trunk/libs/icl/; revision=82958
Simplifying operator = implementations with move using call by value ("sink arguments").

svn path=/trunk/boost/icl/; revision=83383