Add a v.mod file. #36

	name: Build and Test

	on: [push, pull_request]

	jobs:
	ubuntu:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout Latest V
	uses: actions/checkout@v2
	with:
	repository: vlang/v
	path: v

	- name: Checkout Coreutils
	uses: actions/checkout@v2
	with:
	path: libsodium

	- name: Install libsodium-dev package
	run: sudo apt-get install --quiet -y libsodium-dev

	- name: Build V
	run: cd v && make && sudo ./v symlink && cd -

	- name: V doctor
	run: v doctor

	- name: Symlink libsodium to ~/.vmodules
	run: ln -s $(pwd)/libsodium ~/.vmodules/libsodium

	- name: Ensure everything is formatted
	run: v fmt -verify ~/.vmodules/libsodium

	- name: Run tests
	run: v test ~/.vmodules/libsodium

	- name: Build example
	run: v -cstrict ~/.vmodules/libsodium/examples/example.v

	- name: Build example with -prod
	run: v -cc clang -cstrict -prod ~/.vmodules/libsodium/examples/example.v

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