Add optional destination folder and get file content

[mpijierro]

Hi,

first of all thanks for your work with this component. It saved me a lot of time.

I would like to propose two very simple changes that I hope are useful.

1. The first is to add an optional destination folder for the downloaded files. If the folder is not specified, the operation is the original with the folder 'dropbox-temp' as the destination.

2. The second is to add a function to get the content of a file without having to download. In this way, it is possible to treat it locally in the most convenient way.

That's all. Thanks again.
Greetings.

[dcblogdev]

thanks this looks like a nice addition, I'll look it over in more detail over the weekend.

[mpijierro]

Sorry, I did a push to master with other added functionality. I have left the pull request as it was originally.

Thanks for your time