Removing the obsolete promotions for reductions

[kimikage]

The current codebase has no compatibility with Julia v0.6, because the syntax for parametric methods has been fully changed to the current (i.e.where) style. I think the backporting is not easy. Therefore, the following codes are no longer useful.

FixedPointNumbers.jl/src/FixedPointNumbers.jl

Lines 157 to 169 in 70ae1d6

 if isdefined(Base, :r_promote) 
     # Julia v0.6 
     Base.r_promote(::typeof(+), x::FixedPoint{T}) where {T} = Treduce(x) 
     Base.r_promote(::typeof(*), x::FixedPoint{T}) where {T} = Treduce(x) 
     Base.reducedim_init(f::typeof(identity), 
                    op::typeof(+), 
                    A::AbstractArray{T}, region) where {T <: FixedPoint} = 
                        Base.reducedim_initarray(A, region, zero(Treduce)) 
     Base.reducedim_init(f::typeof(identity), 
                    op::typeof(*), 
                    A::AbstractArray{T}, region) where {T <: FixedPoint} = 
                        Base.reducedim_initarray(A, region, oneunit(Treduce)) 
 else 

Removing the obsolete promotions may help improve the promotion rules. For example, the current promotions use const Treduce = Float64, but I don't think it is always pretty good. (I can expect the negative impact of the braking change to be significant, though.)
Moreover, it ostensibly improves the code coverage.