Merge branch 'configurable-methods'

docs/site-example/site.conf

docs/user/site.rst

package/gluon-luci-mesh-vpn-fastd/Makefile

package/gluon-luci-mesh-vpn-fastd/check_site.lua

...iles/usr/lib/lua/luci/controller/admin/mesh_vpn_fastd.lua

...files/usr/lib/lua/luci/model/cbi/admin/mesh_vpn_fastd.lua

...s/usr/lib/lua/luci/view/gluon/cbi/mesh-vpn-fastd-mode.htm

package/gluon-luci-mesh-vpn-fastd/i18n/de.po

...on-luci-mesh-vpn-fastd/i18n/gluon-luci-mesh-vpn-fastd.pot

.../gluon-luci-theme/files/www/luci-static/gluon/cascade.css

package/gluon-luci-theme/sass/cascade.scss

package/gluon-mesh-vpn-fastd/check_site.lua

...mesh-vpn-fastd/files/lib/gluon/upgrade/400-mesh-vpn-fastd