Merge pull request #459 from kanoi/master

miner.php add ASC fields
Merge pull request #460 from kanoi/master

Update all screen A/R to instead use DA/DR and device U to WU
Just display A: and R: for difficulty accepted and rejected to preserve screen real estate and decrease decimal places for WU.
Allow the avalon fanspeed range to be passed as parameter on the command line, default to 20-100%
Use a more conservative upper limit of 1% for hardware errors with avalon auto frequency.
Don't count invalid nonces as hashrate for bflsc.
Decrease avalon frequency in auto mode if we are unable to maintain the temperature in the optimal range.
Set the avalon idle frequency to lowest if avalon auto is enabled and we have an overheat condition.
Provide an --avalon-freq command line to give a valid range of frequencies for avalon in auto mode.
Set avalon fan min and fan max to PWM values instead of percentage.
Add more information about avalon-fan and avalon-freq to ASIC-README
Reinstate more aggressive <2% HW error target for avalon-auto
Only throttle avalon clockspeed in avalon_auto in non optimal temperature settings if the fanspeed has reached maximum.
Convert the decay_time function into one that truly creates an exponentially decaying average over opt_log_interval.
Fix potential dereference when starting avalon with all new work.
Count the number of miners idled in avalon to account more accurately for when its result return rate is too low.
Decay result count in avalon more slowly to not falsely detect idle periods as low result return rates.
Check for a timeout in avalon_scanhash and post to the write sem if we receive one.