Have install.php check if necessary server tweaks are done

[kaguy4]

install.php file should check and output if necessary configs for koko to work are properly installed, like this:

checking if mbstring is enabled... -> TRUE (colored green)

checking if gd is enabled... -> TRUE

or if it's false:

checking if mbstring is enabled... -> FALSE (colored red) -> On Debian based systems, run sudo apt install php-mbstring -> If it persists, read this manual -> Remember to reload apache&nginx after enabling

checking if gd is enabled... -> FALSE -> go to php.ini and uncomment gd -> if you don't see gd but gd2, leave it disabled, but add extension=gd under it -> Remember to reload apache&nginx after enabling

Maybe it should also check stuff about the uploading process, liek: -> (colored yellow)Warning: upload_max_filesize on php.ini is set default 2MB. You may need to increase it for file uploads. Read this manual for more information. Remember to reload nginx&apache2 after changing the value.

I don't know all necessary stuff that often don't come pre-installed/done, but here are some that were mentioned in a recent discussion: gd, pdo_mysql, php_mysqli, ffmpeg, mbstring

[kaguy4]

while on it, "database successfully set up" message should be followed by a link to koko.php