Add ctype functions
  - isalnum
  - isalpha
  - isascii
  - isdigit
  - islower
  - isspace
  - isupper
Add stdlib functions
  - atoi
  - atol
Fix some warnings
Make a fmt run

Update platform support for linux to avoid the use of syscalls not
supported by Aarch64.
  - link, chown, and open should use fchownat and linkat with fd
    set to AT_FDCWD.
  - use dup3 with the 3rd arg set to 0 instead of dup2.

Add cargo fmt script

 - Add a rustfmt config
 - Get the current code passing the formatter

Dan Robertson authored 7 years ago and Dan Robertson committed 7 years ago

 - Add cfg to extern crate sc. It is not used by redox.
 - Fix bad syntax in brk implementation for redox
 - nits
   - style: update brk implementation for linux
   - style: no space between not operator and ptr.is_null
   - style: should be a space around = in module path