Rust

Optionally support openssl instead of boringssl backend #275

	name: Rust

	on:
	- push
	- pull_request

	env:
	CARGO_TERM_COLOR: always

	jobs:
	build:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	- name: build
	run: cargo build
	- name: build with cwt
	run: cargo build --features="cwt"
	- name: pure rust implementation
	run: cargo build --no-default-features --features="pure-rust"
	- name: openssl implementation
	run: cargo build --no-default-features --features="openssl"
	- name: wasm32-freestanding build
	run: \|
	rustup target add wasm32-unknown-unknown
	cargo build --verbose --target=wasm32-unknown-unknown
	- name: wasi32-wasi build
	run: \|
	rustup target add wasm32-wasi
	cargo build --verbose --target=wasm32-wasi
	- name: Run tests
	run: cargo test --verbose

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