Add .dropboxignore directory to exclude folders without using selective sync

Hi folks, 

Thanks for your feedback on this.
While ignored files delivers for some of the use cases here, I appreciate it does not for all. 
We'll be taking another review of this thread to isolate use cases for a .dropboxignore file feature in particular.

I've updated the status and we'll take this to the product team.
As a side note, it would be helpful for us if you could outline the gap between what ignored files offers, and what a .dropboxignore file feature would add to your workflows.

Thank you.