Raysync Software v5.0.7.8

What's new on Raysync v5.0.7.8

1. Support preview files, pictures and videos online
2. Add video preview watermark settings
3. support the identification of different devices in the external network environment on node management
4. Add the period setting of the maximum speed
5. Support national encryption standard
6. RaySSH supports MacOS client
7. Add speed unit configuration: Bit/Byte
8. Add importing accounts by AD domain group
9. optimize command line
10. fix some bugs