New Authentication

I am partially finished implementing a new authentication protocol for 1.0

### Features:
 [x] Prompt user to login if they are doing operation that requires authentication
 [ ] Add better error and console logging 
 [x] Added IP, hostname, and other metadata to authentication tokens
 [x] Added resource restiction to authentication tokens
 [x] Added auth sub command
 [ ] Update api,conda and pypi sites to handle new tokens
 [x] Added -t/--token command line argument for non-permanent logins

### Auth Sub Command help:

```
$ binstar auth -h
usage: binstar auth [-h] [-n NAME] [--url URL] [--max-age MAX_AGE]
                    [--resource RESOURCE] (-l | -r ID [ID ...] | -c)

Manage Authentication tokens

optional arguments:
  -h, --help            show this help message and exit
  -n NAME, --name NAME  The name of the application that will use this token
  --url URL             The url of the application that will use this token
  --max-age MAX_AGE     The maximum age in seconds that this token will be
                        valid for
  --resource RESOURCE   The resource path that this token is valid
  -l, --list            list all user authentication tokens
  -r ID [ID ...], --remove ID [ID ...]
                        remove authentication tokens
  -c, --create          Create an authentication token
```

### Example use cases: 

1. Authenticate temporary token to upload a single package (*username/package_name*) without logging in available for 10 minutes:

```bash
$ TOKEN=$(binstar auth -c --resource 'api:/*/username/package_name/**' --max-age=600)
Username: sean
Password: ****

binstar -t $TOKEN upload package_name.tar.bz2
```