ExpressLRS V1.0.0 RC9 Release

As always, arming must be on AUX1 for safety and performance

Thanks to everyone who gave feedback and reported issues, changes as follows:

Enhancements

• Added targets for Happy Model ES900RX and ES900TX (#712)

Fixes

• 500hz is now set by default. 25Hz mode has been removed from 2.4GHz (#676)
• Fix MSP for 500hz update rate (#705)
• Fix RX locking up coming out of bind (#675)
• Fix r9slim rx enable pin (#710)
• Fix R9 lite pro output power on boot. Added additional low power modes. (#709)