R: Vignettes and other documentation

# Vignettes and other documentation

## Vignettes from package 'openeo'

openeo::openeo-01-getting_started |  | Getting Started | HTML | source | R code
openeo::openeo-02-sample_data |  | Sample Data Retrieval | HTML | source | R code
openeo::openeo-03-package-software-architecture |  | Software and Package Architecture | HTML | source |
openeo::openeo-04-process_graph_concepts |  | Process Graph Building | HTML | source | R code
openeo::openeo-05-process_graph_building_application |  | Process Graph Building Application | HTML | source | R code
openeo::openeo-06-developer_implementation_details |  | Developer Implementation Details | HTML | source | R code