Betaflight 2.1.1

#Bugfixes:
Fixed broken Beeper function. No beeper when no VBAT connected

#Features:

• Enhanced pid_at_min_throttle. You can now use higher values than 0 or 1. "set pid_at_min_throttle = 2" means that Iterm will be reset after 2 seconds and maximum configurable setting is 5seconds. 0 and 1 will act the same as before. This is yet experimental feature.
• Added new target IRCFUSIONF3 for Vortex Pro
• Baro code optimized to prevent looptime jumps
• Baro and Mag enabled by default. Set to "set baro_hardware = 1" and "set mag_hardware = 1" to disable again

Betaflight 2.1.0

New Betaflight Release Version Management. It was becoming a mess to keep binaries in the source.
This should be more clear for everyone.

Quick summary of main flight performing features in betaflight:

• Gyro sync (always the most fresh gyro data before the loop starts with minimum delay)
• Overclocked i2c bus to speed up communication with gyro
• Gyro FIR filter preconfigured forthe cleanest gyro traces to the pid controller
• Optimized D calculations and filtering for more derivative precision
• Optimized defaults with main focus on PID1 and PID2 (reduced amount of pid controllers for better overview)
• On F1 targets no need to disable acc anymore to get same performance. Gyro readings get priority when in acro mode.
• Optimized scheduling in tasks to minimize jitter to motors
• Fast PWM support in combination with Oneshot125 (This is usefull when you want fixed refresh rate for ESC's up to 4khz)
• Easy to no tuning. Stock settings for PID1 and PID2 should be very well flyable on most machines. The optimised filters do good job on feeding the cleanest gyro traces to the pid controller loop, which gives better flight experience and easier tuning.
• Cooler motors and ESC's. Better for equipment due to clean filters.
• Quaternion logic for Level modes. More precision, less drift and faster performance!
• Beeper selectable for different events
• ESC passtrhough programming through Cleanflight