Modify `Storage` trait to return number of written bytes to the cache. #635

	name: CI
	on: [push, pull_request]

	jobs:
	build:
	name: Build and test
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	override: true
	- name: Build
	run: \|
	cargo build

	rustfmt:
	name: Rustfmt
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	components: rustfmt
	override: true
	- run: cargo fmt -- --check

	clippy:
	name: Clippy check
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	components: clippy
	override: true
	- uses: actions-rs/clippy-check@v1
	with:
	token: ${{ secrets.GITHUB_TOKEN }}

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