UCI network already permit dialnumber option for 3g interfaces.
This adds dialnumber to luci protocol 3g. Also it introduces a
new translation string "Dial number", added to template and updated
on each language (all empty but pt-br).

Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>

 * Rename subdirectories to their repective OpenWrt package names
 * Make each LuCI module its own standalone package
 * Deploy a shared luci.mk which is used by each module Makefile

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>