FEATURE: Improve site:list command

[crydotsnake]

Upgrade instructions

None

Review instructions

Improves our ./flow site:list command by render the list of all available sites directly in a table.

Checklist

• [x] Code follows the PSR-2 coding style
• [x] Tests have been ~created~, run and ~adjusted~ as needed
• [ ] The PR is created against the lowest maintained branch
• [x] Reviewer - PR Title is brief but complete and starts with FEATURE|TASK|BUGFIX
• [ ] Reviewer - The first section explains the change briefly for change-logs
• [ ] Reviewer - Breaking Changes are marked with !!! and have upgrade-instructions

[mhsdesign]

Noice thanks a lot @crydotsnake you can read my mind!!!