Cleaner Output

Hi,
This pull is my personal preference and it may exist scenarios I haven't thought of. 

I'm using grunt-hub in a client/server senario where I have two grunt-projects in which I want to be able to run grunt tasks at the same time as simple as possible. 

With this code I get the following print.. (my full paths excluded)

```
$ grunt dev
Running "hub:dev" (hub) task
>> Running [dev] on /[...]/server/Gruntfile.js
>> Running [dev] on /[...]/client/Gruntfile.js


>> /[...]/server/Gruntfile.js:

Running "shell:server" (shell) task

Running "watch" task
Waiting...

>> /[...]/client/Gruntfile.js:

Running "connect:client" (connect) task
Started connect web server on localhost:8080.

Running "watch" task
Waiting...

>> /[...]/server/Gruntfile.js:

Server listening at http://0.0.0.0:8081
```

where the code in the master produced a lot of newlines...