r82xx: register caching
r82xx: register batching
lib: cache i2c repeater
r82xx: pll tweaks beyond my ken
r82xx: error on pll failure
rtl_test: r820t tuning range
r82xx: build warning
rtl_fm: half working AGC
rtl_fm: wav header
rtl_fm: mostly working AGC
lib: retry i2c on failure
rtl_fm: proportional squelch
rtl_fm, power: stay open through broken pipes
rtl_sdr: units on -n
rtl_fm: half finished stream padding
rtl_power: fixed size bins, refactoring
rtl_power: adjustable sample rate
rtl_power: multiple frequency ranges
rtl_power: linear output
r82xx: improved tuner precision

Improve tuner precision by calculating the VCO divisor at full precision,
not at kHz resolution. Also replace the manual divison loop with a
simpler fixed-point calculation.