Increase Time Notification is Displayed

[sam3k]

Right now, the notification fades out way to quick when there is more than one message; not giving enough time to read the message. This was my case when getting notifcations from Karma:

Warning: Task "karma:ci" failed. Use --force to continue.

Aborted due to warnings.

First message seems to be overridden by the second not giving enough time to read it.

[dylang]

If you are using snarl I've fixed the issue.

If you are using OS X Notification Center there is no way to change the way it works unfortunately.

[dylang]

Oh yeah, forgot to say I just released `Grunt-Notify 0.2.8. It should hopefully address this issue. Let me know if you run into this again or other issues. Thanks for your support.