Tools: gittools: add scripts that list subsystems

Those scripts print a list of subsystems (first level folders and libraries).
They are useful for other future tools.

Tools/gittools/path-libraries.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+usage() {
+    cat >&$1 <<EOF
+Usage: $0 [OPTIONS]
+
+Read a list of files relative to ardupilot's root directory and output the
+libraries they belong to.
+
+Options:
+    --show-paths, -p    Print also file paths after the library name.
+    --help, -h          Show this help message.
+EOF
+}
+
+show_paths=false
+
+while [[ -n $1 ]]; do
+    case "$1" in
+    --show-paths|-p)
+        show_paths=true
+        ;;
+    --help|-h)
+        usage 1
+        exit 0
+        ;;
+    *)
+        usage 2
+        exit 1
+        ;;
+    esac
+
+    shift
+done
+
+if $show_paths; then
+    sedcmd="s,libraries/\([^/]\+\).*,\1\t\0,"
+else
+    sedcmd="s,libraries/\([^/]\+\).*,\1,"
+fi
+
+grep "^libraries/[^\/]\+" | \
+    sed $sedcmd | \
+    sort | \
+    uniq

Tools/gittools/path-nonlibraries.sh

@@ -0,0 +1,57 @@
+#!/bin/bash
+
+usage() {
+    cat >&$1 <<EOF
+Usage: $0 [OPTIONS]
+
+Read a list of files relative to ardupilot's root directory and output the
+non-libraries subsystems they belong to.
+
+Options:
+    --show-paths, -p    Print also file paths after the library name.
+    --help, -h          Show this help message.
+EOF
+}
+
+show_paths=false
+
+while [[ -n $1 ]]; do
+    case "$1" in
+    --show-paths|-p)
+        show_paths=true
+        ;;
+    --help|-h)
+        usage 1
+        exit 0
+        ;;
+    *)
+        usage 2
+        exit 1
+        ;;
+    esac
+
+    shift
+done
+
+SCRIPT_DIR=$(dirname $(realpath ${BASH_SOURCE[0]}))
+ROOT=$(dirname $(git -C $SCRIPT_DIR rev-parse --git-dir))
+
+if $show_paths; then
+    sedcmd="s,\([^/]\+\).*,\1\t\0,"
+else
+    sedcmd="s,\([^/]\+\).*,\1,"
+fi
+
+grep -v "^libraries" | \
+    sed $sedcmd | \
+    sort | \
+    uniq | \
+    if $show_paths; then
+        while read d f; do
+            [[ -d "$ROOT/$d" ]] && printf "%s\t%s\n" "$d" "$f"
+        done
+    else
+        while read d; do
+            [[ -d "$ROOT/$d" ]] && echo "$d"
+        done
+    fi