add tomatos support?

your pomo list can be like this:

```sh
$ pomo ls
    0. modify for order task                              : 1 tomatos
    1. learn rails activepack                             : 2 tomatos
    2. learn haskell                                      : 1 tomatos
    3. learn programming                                  : 1 tomatos
                                              0 minutes and 5 tomatos
```