Remove spurious path::make_absolute() signature from synopsis - it was removed from class path in 2010 in favor of absolute() non-member operational function.

svn path=/trunk/libs/filesystem/; revision=80163
Fix #7239, Stack overflow when calling create_directories(":D"). The reported problem was a symptom of an internal bug that caused path::filename() and path::parent_path() to fail on Windows for path(":"), and that in turn caused other functions that depend on filename() or parent_path() to fail, such as create_directories().

svn path=/trunk/libs/filesystem/; revision=80279
Doc fixes

svn path=/trunk/libs/filesystem/; revision=80613
System/FileSystem/Asio/Thread: ref #7278 Added noexcept to Boost.System to conform with C++11

svn path=/trunk/libs/filesystem/; revision=81808