Returns a BigNumber whose value is the minimum of the arguments.

The return value is always exact and unrounded.

x = new BigNumber('3257869345.0378653')
BigNumber.min(4e9, x, '123456789.9')             // '123456789.9'

arr = [2, new BigNumber(-14), '-15.9999', -12]
BigNumber.min.apply(null, arr)                   // '-15.9999'