ate number of coeffs for a particular style
all specified temperatures are in temperature units
target temperature at intermediate points during run is a ramped value
  between the beginning and ending temperatures
for rescale style, temperature is controlled by explicitly rescaling
  velocities towards the target temperature
for rescale style, rescaling is only done if current temperature is
  beyond the target temperature plus or minus the window value
for rescale style, the amount of rescaling is contfol