Added Overlay OnClickListener, PlayInSequence, Next method

[aaronliew]

hihi,

Awesome library! Have a look at the changes!

Regards,
workerApe

[worker8]

Thanks for the many commits!

I realize that you are actually working on a few separate features that are not relevant to each other. Can you separate them into different branches and submit as different pull request?

The reason behind this is because there will be some back and forth, for example: I might have some feedback on commit 1, and you might need to do changes on commit 1, but commit 2 is ready to be merged, but I couldn't merge yet due to commit 1 still having to change.

Besides, it is easier for discussion when each relevant feature is in each individual branches, and also easier for me to understand your code.

From what I can see, you are working on:

• Overlay listener feature
• Convenience method for playing in sequence feature
• Method to check if TourGuide is showing

So ideally you should have 3 branches and 3 pull requests (it is alright for feature and the relevant example to go under the same branch).

Thanks again!