From the user, we are given a wind value and the unit to convert.
To convert between miles per hour (mph) and knots (kts):
To convert between miles per hour (mph) and meters per second (m/s):
To convert between miles per hour (mph) and feet per second (ft/s):
To convert between miles per hours (mph) and kilometers per hour (km/h): 
To convert between knots (kts) and meters per second (m/s):
To convert between knots (kts) and feet per second (ft/s):
To convert between knots (kts) and kilometers per hour (km/h):
To convert between meters per second (m/s) and feet per second (ft/s):
To convert between meters per second (m/s) and kilometers per hour (km/h):
To convert between feet per second (ft/s) and kilometers per hours (km/h):
