onClick fix + new onClose callback

[IgorKvasn]

Hi,
I noticed, that when onClick callback is defined and user clicks on the close icon, the onClick callback is triggered. I am not sure if it is desired or not, but I don't like this behavior :) Usually close button basically means "ignore the notification and carry on" - by triggering the callback you are basically performing an action that user wanted to ignore.

So I fixed it (onClick callback will be triggered when clicking anywhere on the notification except the close icon) + I added new onClose callback that will be triggered when user closes the notification

btw. I know that the way I fixed the onClick callback in method mouseDown() is not very nice (jQuery...), but it works anyway...

[IgorKvasn]

hmm I just noticed, that changes from my previous pull request #78 also appear in this PR... sorry about that - if it is more convenient for you, I can remove #78 code from this PR... or you can just accept this PR and close the #78 :)

[ynnoj]

@IgorKvasn Could you rebase please?

[ynnoj]

@IgorKvasn Going to close this as the branch is significantly out of date now. Please submit an up-to-date PR.