add postinst from debian

debian/trojita.postinst

@@ -0,0 +1,25 @@
+#!/bin/sh
+# postinst script for #PACKAGE#
+#
+# see: dh_installdeb(1)
+
+set -e
+
+case "$1" in
+    configure)
+        # not needed: ldconfig /usr/lib/x86_64-linux-gnu/libtrojita_plugins.so
+        true
+    ;;
+
+    abort-upgrade|abort-remove|abort-deconfigure)
+    ;;
+
+    *)
+        echo "postinst called with unknown argument \`$1'" >&2
+        exit 1
+    ;;
+esac
+
+#DEBHELPER#
+
+exit 0