add cmath and/or _USE_MATH_DEFINES for MSVC in proj4 files #63

	name: DGGRID GitHub Actions CI

	on:
	push:
	branches: [master,win-math,dev,develop,'patch-','feature-']
	pull_request:
	branches: [master]

	jobs:
	tests:
	name: DGGRID Earthly build
	runs-on: ubuntu-latest
	steps:
	- uses: earthly/actions-setup@v1
	with:
	github-token: ${{ secrets.GITHUB_TOKEN }}
	version: "latest"
	- uses: actions/checkout@v2
	- name: what version is installed?
	run: earthly --version
	- name: Login to Github Docker Registry (id not PULL)
	if: ${{ github.event_name != 'pull_request' }}
	run: echo "${{ secrets.GHCR_TOKEN }}" \| docker login ghcr.io -u ${{ github.repository_owner }} --password-stdin
	- name: run the Earthly +test target
	run: earthly +test
	- name: Push image (if not PULL)
	if: ${{ github.event_name != 'pull_request' }}
	run: \|
	IMAGE_ID=ghcr.io/${{ github.repository_owner }}/dggrid

	# Change all uppercase to lowercase
	IMAGE_ID=$(echo $IMAGE_ID \| tr '[A-Z]' '[a-z]')
	# Strip git ref prefix from version
	VERSION=$(echo "${{ github.ref }}" \| sed -e 's,./$.$,\1,')
	# Strip "v" prefix from tag name
	[[ "${{ github.ref }}" == "refs/tags/"* ]] && VERSION=$(echo $VERSION \| sed -e 's/^v//')
	# Use Docker `latest` tag convention
	[ "$VERSION" == "master" ] && VERSION=latest
	echo IMAGE_ID=$IMAGE_ID
	echo VERSION=$VERSION
	# docker tag $IMAGE_NAME $IMAGE_ID:$VERSION
	# docker push $IMAGE_ID:$VERSION
	earthly --push +docker-github --imagetag=$IMAGE_ID:$VERSION

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