update affected websites when a directive snippet was updated (Implements #5632)

install/sql/incremental/upd_dev_collection.sql

install/sql/ispconfig3.sql

interface/web/admin/directive_snippets_edit.php

interface/web/admin/form/directive_snippets.tform.php

interface/web/admin/lib/lang/ar_directive_snippets.lng

interface/web/admin/lib/lang/bg_directive_snippets.lng

interface/web/admin/lib/lang/br_directive_snippets.lng

interface/web/admin/lib/lang/ca_directive_snippets.lng

interface/web/admin/lib/lang/cz_directive_snippets.lng

interface/web/admin/lib/lang/de_directive_snippets.lng

interface/web/admin/lib/lang/dk_directive_snippets.lng

interface/web/admin/lib/lang/el_directive_snippets.lng

interface/web/admin/lib/lang/en_directive_snippets.lng

interface/web/admin/lib/lang/es_directive_snippets.lng

interface/web/admin/lib/lang/fi_directive_snippets.lng

interface/web/admin/lib/lang/fr_directive_snippets.lng

interface/web/admin/lib/lang/hr_directive_snippets.lng

interface/web/admin/lib/lang/hu_directive_snippets.lng

interface/web/admin/lib/lang/id_directive_snippets.lng

interface/web/admin/lib/lang/it_directive_snippets.lng