add geographiclib install script

sitl_config/mavros/install_geographiclib_datasets.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+# Script to install the model datasets required
+# to GeographicLib apply certain conversions
+
+if [[ $UID != 0 ]]; then
+	echo "This script require root privileges!" 1>&2
+	exit 1
+fi
+
+# Install datasets
+run_get() {
+	local dir="$1"
+	local tool="$2"
+	local model="$3"
+
+	files=$(shopt -s nullglob dotglob; echo /usr/share/GeographicLib/$dir/$model* /usr/local/share/GeographicLib/$dir/$model*)
+	if (( ${#files} )); then
+		echo "GeographicLib $tool dataset $model already exists, skipping"
+		return
+	fi
+
+	echo "Installing GeographicLib $tool $model"
+	geographiclib-get-$tool $model >/dev/null 2>&1
+	
+	files=$(shopt -s nullglob dotglob; echo /usr/share/GeographicLib/$dir/$model* /usr/local/share/GeographicLib/$dir/$model*)
+	if (( ! ${#files} )); then
+		echo "Error while installing GeographicLib $tool $model"
+		return
+	fi
+}
+
+# check which command script is available
+if hash geographiclib-get-geoids; then
+	run_get geoids geoids egm96-5
+	run_get gravity gravity egm96
+	run_get magnetic magnetic emm2015
+elif hash geographiclib-datasets-download; then # only allows install the goid model dataset
+	geographiclib-datasets-download egm96_5;
+else
+	echo "OS not supported! Check GeographicLib page for supported OS and lib versions." 1>&2
+fi