Code Review: bugs-1

tfpt review “/shelveset:bugs-1;REDMOND\jflam”
Comment :
Fixes Rakefile to correctly generate case-sensitive filenames during
Fixes String#reverse and taint flow
Fixes File#zero? behavior (works correctly for directory names, and
handles NUL correctly)
Stubs out implementation of File#symlink do throw a
NotImplementedError (not sure if we can do this without P/Invoke)

Looks good.