whoami: fix for Windows
Move whoami from UNIX_PROGS to PROGS
whoami: change GetUserName to GetUserNameA
Merge pull request #251 from Arcterus/whoami

whoami: fix for Windows
add nl
Merge pull request #238 from tobstar87/nl

implemented "nl"
nl: remove to_err_msg (deprecated)
c_types: fix c_group (struct group) memory layout
c_types: use libc::{uid_t,gid_t} where appropriate
id: use libc::{uid_t,gid_t} where appropriate
whoami: use libc::uid_t where appropriate
c_types: handle errors from getgroups()/getgrouplist()
Merge pull request #253 from ebfe/fix-c-group

c_types: fix c_group (struct group) memory layout
Merge pull request #254 from ebfe/groups

c_types: handle errors from getgroups()/getgrouplist()
id: fix on Macs
Common function to get user group info
chroot implementation
Remove chroot from todo list
Remove unused debug crate import
Code style fixes