Signed-off-by: Michael Heimpold <mhei@heimpold.de>

This is a copy of the existing php5 stuff, adopted for PHP7.

Please not, that its not supported to install both php5
and php7 in parallel on the target.

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

Signed-off-by: wuqiong <memccpy@gmail.com>

- split fpm config into main and pool file
- introduced uci config file
- re-worked init script

Signed-off-by: Michael Heimpold <mhei@heimpold.de>