Add a "Share" radio button in addition to URL, Local and Page

[libreliodev]

When this button is selected, do not display the full screen and autoplay options.

Instead, display the following input fields:

• Image to share: give the choice between the existing images in the publication folder, or upload a new image
• Destination: use a check box with 3 options: Facebook, Twitter, Mail.
• Title
• Text
• Link

Based on all these input, the link to add to the pdf should be
share://librelio-europe.s3.amazonaws.com/[Publisher Name]/[App name]/[Publication folder]/[Name of image to share]?wasites=facebook,twitter,mail[or only those selected]&watitle=[URL encoded Tiltle]&watext=[URL encoded text]&walink=[URL encoded link]

Reciprocally, when the user selects a "share://..." link, make sure the input fileds are correctly displayed, by parsing the url.