php7 install memcached extension

#download source code package from git 
$ git clone https://github.com/php-memcached-dev/php-memcached.git
$ cd php-memcached
$ git checkout php7    
#Branch php7 set up to track remote branch php7 from origin.
#Switched to a new branch ‘php7‘
$ /home/admin/local/php7/bin/phpize
$ ./configure --with-libmemcached-dir=/home/admin/local/libmemcached-0.53/ --with-php-config=/home/admin/local/php7/bin/php-config
  --disable-memcached-sasl

$make && make install