updated build documentation to require boost-1.49. regenerate html

git-svn-id: http://libtorrent.googlecode.com/svn@10031 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
some more fixes of get_system_category()

git-svn-id: http://libtorrent.googlecode.com/svn@10032 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
use std::chrono if available, otherwise boost::chrono (stay in sync with what boost.asio uses)

git-svn-id: http://libtorrent.googlecode.com/svn@10033 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
more build and run-time fixes

git-svn-id: http://libtorrent.googlecode.com/svn@10034 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
some more runtime fixes from switching to boost::chrono

git-svn-id: http://libtorrent.googlecode.com/svn@10035 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
even more runtime fixes from switching to boost::chrono

git-svn-id: http://libtorrent.googlecode.com/svn@10036 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
one more fix

git-svn-id: http://libtorrent.googlecode.com/svn@10037 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
windows build fixes

git-svn-id: http://libtorrent.googlecode.com/svn@10038 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
attempted gcc fix

git-svn-id: http://libtorrent.googlecode.com/svn@10039 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
another attempt at fixing piece_picker static assert on gcc

git-svn-id: http://libtorrent.googlecode.com/svn@10040 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda