add skeleton for new Nominatim executables

cmake/tool.tmpl

@@ -0,0 +1,11 @@
+#!/usr/bin/env python3
+import sys
+
+sys.path.insert(1, '@CMAKE_SOURCE_DIR@')
+
+from nominatim import tools
+
+tools.@tool_name@(module_dir='@CMAKE_BINARY_DIR@/module',
+                  osm2pgsql_path='@CMAKE_BINARY_DIR@/osm2pgsql/osm2pgsql',
+                  phplib_dir='@CMAKE_SOURCE_DIR@/lib',
+                  data_dir='@CMAKE_SOURCE_DIR@')