updating growl dependency

[benjamine]

this updates to last version of growl ( from tj/node-growl#57 )
this for example fixes the way notifications look in OSX (they don't show a success/fail icon currently), with this update now it looks like this:

[danielstjules]

Hey! Sorry, using the tilde breaks compatibility with old versions of npm #2121 (comment)

We've also had a history of things breaking when bumping dependencies. If any of growl's dependencies use a tilde or don't use strict enough versioning, we could indirectly introduce future issues.

For example, with your current branch:

$ grep "mocha" package.json
    "mocha": "benjamine/mocha#master"
danielstjules:~/git/testing
$ node --version
v0.10.11
danielstjules:~/git/testing
$ npm --version
1.2.30
danielstjules:~/git/testing
$ npm install
...
npm ERR! Valid install targets:
npm ERR! ["1.0.1","1.0.2","1.1.0","1.2.0","1.2.1","1.3.0","1.4.0","1.4.1","1.5.0","1.5.1","1.6.0","1.6.1","1.7.0","1.8.0","1.8.1","1.9.0","1.9.1","1.9.2"]
npm ERR!     at installTargetsError 

[benjamine]

@danielstjules that's perfect!, fixed

[danielstjules]

Looks good, everything correctly installs with this latest version of the branch. :) And added bonus that we don't need to worry about nested dependencies, since growl doesn't have any.

Thanks!