update history ac 3.1.5
add AntennaTracker to firmware list
ap3.1.1
ar 2.47
ac3.1.5
at 0.2
Added link to latest and beta firmwares
VRBRAIN: modified link for old VRBRAIN 4 boards
Merge pull request #4 from virtualrobotix/for_merge

Added link to latest and beta firmwares