PHP pkg-readme clarification

The current PHP package readme states that all one has to do to run
the Apache PHP module is make a symbolic link. That's only true if
you have the php-apache package installed. If it isn't installed the
supplied command making a symbolic links works (because of the -f) but
it does nothing since the /var/www/conf/modules.sample directory isn't
there and/or doesn't contain the php.conf we are linking. I think it is
fallout from the (appreciated) split so using PHP didn't pull in Apache.

This is just a small wording addition/change to make explicit that the
php-apache package must be installed for it to work.

--Kurt

Index: files/README-main
===================================================================
RCS file: /cvs/ports/lang/php/files/README-main,v
retrieving revision 1.8
diff -u -p -r1.8 README-main
--- files/README-main 23 Jan 2019 21:04:53 -0000 1.8
+++ files/README-main 29 Jan 2019 19:42:39 -0000
@@ -55,8 +55,9 @@ the two; therefore bugs in php can poten
Another option is to use FastCGI via php-fpm as in the above section;
you can use mod_proxy_fcgi to interface it with Apache.

-If you wish to use the Apache module, enable it by creating a
-symbolic link from ${MODPHP_CONFIG_PATH}/modules.sample/php-${PV}.conf
+If you wish to use the Apache module, make sure the php-apache-${PV}
+package is installed. Then the module enable it by creating a symbolic
+link from ${MODPHP_CONFIG_PATH}/modules.sample/php-${PV}.conf
to ${MODPHP_CONFIG_PATH}/modules/php.conf. As root:

ln -sf ${MODPHP_CONFIG_PATH}/modules.sample/php-${PV}.conf \