Fixes/improvements

• [#3621] Fix os.time() being off by one hour
• [#3682] Add error handling to the flash OpenOS program
• [#3764] Fix left and right names being swapped in the Rack GUI
• [#3774] Fix Jukebox driver (kebufu)
• [#3779] Fix os.sleep(0) causing too long without yielding (Ocawesome101)

List of contributors

asie, kebufu, Ocawesome101