Add `skewness` and `kurtosis` for `Radiocarbon`, use effective kurtosis #250

	name: CI
	on:
	push:
	branches:
	- '**'
	paths-ignore:
	- 'README.md'
	- 'examples/**'
	pull_request:
	branches:
	- main
	paths-ignore:
	- 'README.md'
	- 'examples/**'
	jobs:
	test:
	name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	version:
	- '1'
	os:
	- ubuntu-latest
	- windows-latest
	arch:
	- x64
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@v1
	with:
	version: ${{ matrix.version }}
	arch: ${{ matrix.arch }}
	- uses: actions/cache@v1
	env:
	cache-name: cache-artifacts
	with:
	path: ~/.julia/artifacts
	key: ${{ runner.os }}-test-${{ env.cache-name }}-${{ hashFiles('**/Project.toml') }}
	restore-keys: \|
	${{ runner.os }}-test-${{ env.cache-name }}-
	${{ runner.os }}-test-
	${{ runner.os }}-
	- uses: julia-actions/julia-buildpkg@v1
	- uses: julia-actions/julia-runtest@v1
	- uses: julia-actions/julia-processcoverage@v1
	- uses: codecov/codecov-action@v1
	with:
	file: lcov.info
	docs:
	name: Documentation
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@v1
	with:
	version: '1'
	- run: \|
	julia --project=docs -e '
	using Pkg
	Pkg.develop(PackageSpec(path=pwd()))
	Pkg.instantiate()'
	- run: \|
	julia --project=docs -e '
	using Documenter: DocMeta, doctest
	using Chron
	DocMeta.setdocmeta!(Chron, :DocTestSetup, :(using Chron); recursive=true)
	doctest(Chron)'
	- run: julia --project=docs docs/make.jl
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	DOCUMENTER_KEY: ${{ secrets.DOCUMENTER_KEY }}

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