Prepare release. #4

	name: build
	on:
	push:
	tags:
	- 'v[0-9]+.[0-9]+.[0-9]+'
	env:
	CARGO_TERM_COLOR: always
	jobs:
	msrv:
	runs-on: ubuntu-latest
	steps:
	- name: checkout
	uses: actions/checkout@v2
	- name: toolchain
	uses: actions-rs/toolchain@v1
	with:
	toolchain: 1.70.0
	profile: minimal
	components: rustfmt, rust-docs, clippy
	override: true
	- name: test
	uses: actions-rs/cargo@v1
	with:
	command: test
	- name: test-rayon
	uses: actions-rs/cargo@v1
	with:
	command: test
	args: --features rayon
	- name: clippy
	uses: actions-rs/cargo@v1
	with:
	command: clippy
	args: --all
	- name: doc
	uses: actions-rs/cargo@v1
	with:
	command: doc
	- name: doc-rayon
	uses: actions-rs/cargo@v1
	with:
	command: doc
	args: --features rayon
	- name: fmt
	uses: actions-rs/cargo@v1
	with:
	command: fmt
	args: --all --check
	nightly:
	runs-on: ubuntu-latest
	steps:
	- name: checkout
	uses: actions/checkout@v2
	- name: toolchain
	uses: actions-rs/toolchain@v1
	with:
	toolchain: nightly
	profile: minimal
	components: rustfmt, rust-docs, clippy, miri
	override: true
	- name: test
	uses: actions-rs/cargo@v1
	with:
	command: test
	- name: test-rayon
	uses: actions-rs/cargo@v1
	with:
	command: test
	args: --features rayon
	- name: clippy
	uses: actions-rs/cargo@v1
	with:
	command: clippy
	args: --all
	- name: doc
	uses: actions-rs/cargo@v1
	with:
	command: doc
	env:
	RUSTDOCFLAGS: "--cfg docsrs"
	- name: doc-rayon
	uses: actions-rs/cargo@v1
	with:
	command: doc
	args: --features rayon
	env:
	RUSTDOCFLAGS: "--cfg docsrs"
	- name: fmt
	uses: actions-rs/cargo@v1
	with:
	command: fmt
	args: --all --check
	- name: miri
	uses: actions-rs/cargo@v1
	with:
	command: miri
	args: test

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