[freshrss] rewrite guide to use CLI instead of web installer

[EV21]

I also have a few ideas, maybe you can adopt some of them. 🙂

❓ What do you think about variables? So users can do more copy & paste and don't need to build their install command.

[isabell@stardust FreshRSS-latest]$ FRESHRSS_ADMIN_USERNAME='yourFreshRssUsername'
[isabell@stardust FreshRSS-latest]$ FRESHRSS_ADMIN_PASSWORD='yourFreshRssPassword'
[isabell@stardust FreshRSS-latest]$ MYSQL_PASSWORD='yourMySqlPassword'
[isabell@stardust FreshRSS-latest]$ ./cli/do-install.php --default_user ${FRESHRSS_ADMIN_USERNAME} --base_url https://isabell.uber.space --title FreshRSS --api_enabled --db-type mysql --db-host localhost:3306 --db-user ${USER} --db-password ${MYSQL_PASSWORD} --db-base ${USER}_freshrss
...
[isabell@stardust FreshRSS-latest]$ ./cli/create-user.php --user ${FRESHRSS_ADMIN_USERNAME} --password $FRESHRSS_ADMIN_PASSWORD

---

❓ What do you think about using --base_url https://$USER.uber.space instead of --base_url https://isabell.uber.space and just mention a note about it? Or use a variable DOMAIN=https://isabell.uber.space like the other suggestion above

---

❓ I think some default values can be skipped - see https://github.com/FreshRSS/FreshRSS/blob/edge/config.default.php It looks like it should work without --title FreshRSS and --db-host localhost:3306

'title' => 'FreshRSS',
'db' => [
        # Database server
        'host' => 'localhost',
],

---

‼️ Do not use double quotes for passwords like "<yourmysqlpassword>" - use single quotes '<yourmysqlpassword>' so it is handled as a constant string and signs like $, ! or \ will be taken as they are.

[SalocinHB]

Yeah, I thought about using variables when I put together that ugly one-liner. I might switch to that later. If it's merged as-is, feel free to change it in another PR.

For options such as --title, I skipped the ones that are explicitly listed as optional in the FreshRSS CLI installation guide but otherwise stuck to that guide.

[luto]

Thanks! 🎉

@EV21 I fixed the password quotes. Would you like to submit your proposed changes as an additional PR? :)