Create web-preview.get_es.properties

Spanish translation for Document Viewer dashlet.
Create web-preview-config.get_es.properties

Spanish translation for Document Viewer config.
Create pdfjs.get_es.properties

Spanish translation for PdfJs preview options.
Create web-preview.get_es.properties

Spanish translation for FLVPlayer.
Create web-preview.get_es.properties

Spanish translation for MP3Player.
Create web-preview.get_es.properties

Spanish translation for PdfJs options.
Create web-preview.get_es.properties

Spanish translation for Prettify.
Update spin.js to v1.3
README changes to better explain how to enable the viewers in different 4.x versions of Alfresco.
Merge branch 'davidyg-master'