moodle dependencies

I have installed moodle 3.0.3+dfsg-0ubuntu1 on a fresh Ubuntu Xenial minimal system and I have hit two major problems that prevent moodle from running. I believe they can easily be fixed with proper dependencies.

First, when neither mysql nor postgresql are installed, postgresql is automatically installed (moodle recommends "postgresql | mysql-server | virtual-mysql-server"). Accordingly, postgresql-client is also installed (moodle depends on "postgresql-client | mysql-client | virtual-mysql-client"). Fine.

The problem is that moodle also recommends "php-mysql | php-pgsql" and apt then decides to install php-mysql, not php-pgsql. Consequently, when accessing moodle's start page, I got the following error message:

"Error: database driver problem detected.
The site administrator should verify server configuration.
PHP has not been properly configured with the PGSQL extension so that it can communicate with PostgreSQL. Please check your php.ini file or recompile PHP."

I guess the fix is to recommend "php-pgsql | php-mysql" so that it's consistent with other dependencies above.

Second, at the first visit, moodle leads you to a page enumerating all the PHP modules that MUST or SHOULD be present. moodle reports that four of them are missing:

1. php_extension zip MUST be installed and enabled. The Zip PHP extension is now required by Moodle, info-ZIP binaries or PclZip library are not used anymore.

=> This one is a showstopper. moodle should depend on php-zip

2. php_extension mbstring SHOULD be installed and enabled for best results. Installing the optional MBSTRING library is highly recommended in order to improve site performance, particularly if your site is supporting non-Latin languages.

=> moodle should recommend php-mbstring.

3. php_extension soap SHOULD be installed and enabled for best results. Installing the optional SOAP extension is useful for web services and some plugins.

=> moodle should recommend (suggest?) php-soap.

4. php_extension intl SHOULD be installed and enabled for best results. Intl extension is used to improve internationalization support, such as locale aware sorting.

=> moodle should recommend php-intl

Once php-zip, php-mbstring, php-soap and php-intl are installed, apache must be restarted (reloading it is probably enough) and then the moodle installation continues to the next step.

PS: BTW, in moodle's postinst script, there is a check against php5-mysql and php5-pgsql which non longer exist on Xenial (change them to php7.0-mysql and php7.0-pgsql). Personally, I didn't notice any of those error messages during the installation but anyway, they should lead to an "exit 1" in the configure stage.