remove unused simpson function

src/utils.jl

@@ -145,20 +145,6 @@ macro checkinvlogcdf(lp,ex)
     :($lp <= zero($lp) ? $ex : NaN)
 end
 
-# Simple method for integration
-function simpson(f::AbstractVector{Float64}, h::Float64)
-    n = length(f)
-    isodd(n) || error("The length of the input vector must be odd.")
-    s = f[1]
-    t = -1
-    for i = 2:2:n-1
-        @inbounds s += (4 * f[i] + 2 * f[i+1])
-    end
-    s += f[n]
-    return s * h / 3.0
-end
-
-
 # because X == X' keeps failing due to floating point nonsense
 function isApproxSymmmetric(a::Matrix{Float64})
     tmp = true