2.4.0

Added new measures and unit conversions.

• Stiffness - N/m, N/mm, kgf/m
• Torsional Damping - Nms/rad, Nms/deg
• Torsional Stiffness - Nm/rad, Nm/deg
• Torque Pressure Ratio - Nm/Pa, Nm/bar
• Pressure Force Ratio - Pa/N, bar/N
• Specific Energy - Ws/kg, kWh/kg
• Brake Specific Fuel Consumption - kg/Ws, g/kWh
• Airway Conductance - m3/sPa, cm3/sbar