Remove angle (moved to KM3io)

src/math.jl

-Base.angle(d1, d2) = acos(min(dot(normalize(d1), normalize(d2)), 1))
-# TODO: type piracy: this needs to go to KM3io
-Base.angle(a::T, b::T) where {T<:Union{KM3io.AbstractCalibratedHit, KM3io.PMT}} = Base.angle(a.dir, b.dir)
-Base.angle(a, b::Union{KM3io.AbstractCalibratedHit, KM3io.PMT}) = Base.angle(a, b.dir)
-Base.angle(a::Union{KM3io.AbstractCalibratedHit, KM3io.PMT}, b) = Base.angle(a.dir, b)
-
 """
 Calculate the cartesian coordinates for given `ϕ`, `θ` and radius `r`.
 """

test/math_tests.jl

@@ -2,14 +2,6 @@ using NeRCA
 using Test
 
 
-@testset "angle()" begin
-    @test 0 == angle([1,0,0], [1,0,0])
-    @test π/2 ≈ angle([1,0,0], [0,1,0])
-    @test π/2 ≈ angle([1,0,0], [0,0,1])
-    @test π ≈ angle([1,0,0], [-1,0,0])
-end
-
-
 @testset "spread()" begin
     directions = [
         Direction(1.0, 0.0, 0.0),