Remove text on Julia <v.16 limitations from docs

Makes docs more readable and use of Julia v1.0 is very rare.

Author: oschulz

docs/src/index.md

@@ -6,6 +6,6 @@ ChangesOfVariables
 
 This package defines the function [`with_logabsdet_jacobian`](@ref). `(y, ladj) = with_logabsdet_jacobian(f, x)` computes both the transformed value of `x` under the transformation `f` and the logarithm of the [volume element](https://en.wikipedia.org/wiki/Volume_element).
 
-`with_logabsdet_jacobian` supports mapped/broadcasted functions (via `Base.Broadcast.BroadcastFunction` or `Base.Fix1`) and (on Julia >=v1.6) function composition.
+`with_logabsdet_jacobian` supports mapped/broadcasted functions (via `Base.Broadcast.BroadcastFunction` or `Base.Fix1`) and function composition.
 
 Implementations of `with_logabsdet_jacobian(f)` for `identity`, `inv`, `adjoint` and `transpose` as well as for `exp`, `log`, `exp2`, `log2`, `exp10`, `log10`, `expm1` and `log1p` are included.

src/with_ladj.jl

@@ -12,8 +12,7 @@ For `(y, ladj) = with_logabsdet_jacobian(f, x)`, the following must hold true:
 * `ladj` is the `log(abs(det(jacobian(f, x))))`
 
 `with_logabsdet_jacobian` comes with support for broadcasted/mapped functions
-(via `Base.Broadcast.BroadcastFunction` or `Base.Fix1`) and (Julia >=v1.6 only)
-`ComposedFunction`.
+(via `Base.Broadcast.BroadcastFunction` or `Base.Fix1`) and `ComposedFunction`.
 
 If no volume element is defined/applicable, `with_logabsdet_jacobian(f::F, x::T)`
 returns [`NoLogAbsDetJacobian{F,T}()`](@ref).