Version 3.1.0

• Improved the detection and management of files modified during uploads
• Enable previews and thumbnails retrieval from attachments in chat
• Delete inactive users and related incoming shares upon account closing
• Improved management of public key requests for non-contact users
• Added Ubuntu 17.04 to MEGAcmd post-install
• Improvements in compilation scripts for Windows, libuv...
• New functions for chat apps
• Other minor changes
• Bug fixes