bump version 0.3.0 -> 0.3.1 and update CHANGELOG #359

	on:
	push:
	branches:
	- master
	pull_request: {}

	name: Continuous integration

	jobs:
	lint_fuzz_stable:
	name: Lint
	runs-on: ubuntu-latest
	steps:
	- name: Checkout Crate
	uses: actions/checkout@v2
	- name: Install hongfuzz dependancies
	run: sudo apt-get update -y && sudo apt install -y build-essential binutils-dev libunwind-dev libblocksruntime-dev liblzma-dev
	- name: Checkout Toolchain
	uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: 1.58.0
	override: true
	- name: Running fuzzer
	env:
	DO_LINT: true
	run: ./contrib/test.sh

	Nightly:
	name: Nightly - Bench + Docs + Fmt
	runs-on: ubuntu-latest
	steps:
	- name: Checkout Crate
	uses: actions/checkout@v2
	- name: Checkout Toolchain
	uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: nightly
	override: true
	- name: Running benchmarks
	env:
	DO_BENCH: true
	run: ./contrib/test.sh
	- name: Building docs
	env:
	DO_DOCS: true
	run: ./contrib/test.sh

	Int-tests:
	name: Integration tests
	runs-on: ubuntu-latest
	steps:
	- name: Checkout Crate
	uses: actions/checkout@v2
	- name: Checkout Toolchain
	uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- name: Running integration tests
	env:
	DO_BITCOIND_TESTS: true
	run: ./contrib/test.sh

	Tests:
	name: Tests
	runs-on: ubuntu-latest
	strategy:
	matrix:
	rust: [stable, beta, nightly, 1.58.0]
	steps:
	- name: Checkout Crate
	uses: actions/checkout@v2
	- name: Checkout Toolchain
	uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: ${{ matrix.rust }}
	override: true
	- name: Running cargo
	env:
	DO_FEATURE_MATRIX: true
	run: ./contrib/test.sh

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