v1.12.1

Features:

• Attachments (#25, #15)
• Click action (#85)
• Increase FCM priority for high/max priority messages (#70)

Bug fixes:

• Make postinst script work properly for rpm-based systems (#83, thanks @cmeis)
• Truncate FCM messages longer than 4000 bytes (#84)
• Fix listen-https port (no ticket)
• Fix security issue with attachment peaking (#93)