List all package dependencies from a DESCRIPTION file
desc_get_deps(file = ".")DESCRIPTION file to use. By default the DESCRIPTION file of the current package (i.e. the package the working directory is part of) is used.
Data frame with columns: type (dependency type),
package, and version. For non-versioned dependencies
version is *.
Other dependencies: desc_del_deps,
desc_del_dep, desc_has_dep,
desc_set_deps, desc_set_dep