0.1-0 Added split_dir (dir + split_path).
      Added a vignette.
      parent_dir gets a default argument.
      Attempt to fix the problems with CRAN Windows build.
0.0-9 Bug fix release: standardize_path rewritten to fix some cross-platform issues.  In particular it enforces backslashes at the start of UNC paths.
0.0-8 Added create_files fns.
      create_dirs now only tries to create directories that don't already exist.
      temp_dir, temp_file now vectorized & accept paths within temp dir via ... arg. (Minor breaking change.)
0.0-7 Added r_environ(_site), choose_files, choose_dir fns.
      Works with new assertive.* pkgs.
      Some fns no longer return named output.
0.0-6 Fixes for stringr 1.0.0.
0.0-5 Added is_windows_drive, r_profile, get_libraries.
0.0-3 More testing, quality fixes.
0.0-2 First releasable version. Added wrappers to base-R's file and dir 
      functions for consistent syntax and output.  Also added more utility 
      functions and tests.
0.0-1 Added decompose_path and dir_copy.
