docs review: Organization - minor clarifications

[zoltan-david]

Describe the purpose of your pull request

• Clarified that Billing Managers can do Organization Admin things if they are also Org Admins
• The same for Organization Admins doing Billing Manager things
• Updated wording that I found inappropriate eg. "complete" was changed to "full" when the meaning was "entire" and not "completed".

Related issues (only if applicable)

• https://trello.com/c/HsyThkyC/4205-docs-maintenance-week-koncepci%C3%B3-%C3%A9s-feladatkioszt%C3%A1s

How to test? (only if applicable)

• /docs/organization/

Requirement checklist

• I have validated my changes on a test/local environment.
• I have tested that the code snippets I added work. (Leave unchecked if there are no new code snippets.)
• I have added my changes to the V1 and V2 documentations.

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[laliconfigcat]

Suggested change

	The _Organization menu_ is only available for _Organization Admins_ and _Billing Managers_.
	The _Manage Organization menu_ is only available for _Organization Admins_.

The menu name is different, and the manage organization menu is only available for org admins, The billing manager relevant menus are not inside this submenu.