First Alpha Release

First alpha release of vaadin-upload.

Features:

• “Add Files” Button
• Drop Files Support
• Multiple Uploads by Default
• Auto-starting Uploads. All Files are Uploaded Simultaneously
• Limit File Count, File Size, File Types Restrictions
• Detailed Upload Information for Every File
• Events for File Add, File Remove, File Reject, File Upload State Changes
• Customizable Upload XMLHttpRequest with Attributes and Events
• Customizable Server Response Reaction with Event