Add CI workflow for GPU NVHPC build #52

	name: Linux GNU
	# triggered events (push, pull_request) for the master branch
	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]
	workflow_dispatch:

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:

	ubuntu_build:
	name: Ubuntu GNU Build
	# Run on ubuntu-latest
	runs-on: ubuntu-latest

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- name: Checkout repository
	uses: actions/checkout@v2

	# Install OpenMPI
	- name: Install OpenMPI
	run: sudo apt-get install openmpi-bin libopenmpi-dev -y

	# Test debug mode
	- name: Build gf debug
	run: \|
	cd ref
	rm -rf build
	mkdir build
	cd build
	#export OMP_NUM_THREADS=4
	export CC=gcc
	export FC=gfortran
	cmake -DCMAKE_BUILD_TYPE=debug -DENABLE_GPU=off ..
	make
	ctest --output-on-failure

	# Test release mode
	- name: Build gf release
	run: \|
	cd ref
	rm -rf build
	mkdir build
	cd build
	#export OMP_NUM_THREADS=4
	export CC=gcc
	export FC=gfortran
	cmake -DCMAKE_BUILD_TYPE=release -DENABLE_GPU=off ..
	make
	ctest --output-on-failure

Provide feedback