The functions in usermgmt.js are aimed to be a bridge between a
user-level application (mainly the UI), and Samba internals.

The function prototypes are designed by looking at the UI, like for
example:

New User UI (from MMC/Local Users and Groups)

The UI asks for: 
Username
Fullname
Description
Password

and some flags, basically:
    user must change password at next logon
    account is disabled
    user cannot change password
    password never expires

And Samba requires:
    
    unixName 

So, we have the user_add function that does this:

function user_add(sam, username, fullname, description, 
		       password, flags, unixname)

Other functions:

user_delete(sam, username)
user_rename(sam, username, newname)

TODO:
	add/remove users to groups
	user enumeration functions