Function to check whether `FreeSurfer` folder has everything we need
check_freesurfer_path(
fs_subject_folder,
autoinstall_template = FALSE,
return_path = FALSE,
check_volume = FALSE,
check_surface = FALSE
)
logical whether the directory is valid or, if return_path
is true,
return `FreeSurfer` path
character, path to `fs` project directory or `RAVE` subject directory
logical, whether `N27` brain should be installed if missing
logical, whether to return `FreeSurfer` path
logical, whether to check volume data
logical, whether to check surface data (not implemented yet)