[boost] [filesystem] create_directory() & create_directories() return bool

From: Beman Dawes (bdawes_at_[hidden])
Date: 2004-03-11 11:23:06

create_directory() no longer throws if the directory already exists. 
create_directory() and create_directories() now return a bool indicating if 
a directory was actually created.

Both throw if the path argument exists and is not a directory.

Docs and test cases updated accordingly.

--Beman