Create Plone site administrator guide

[stevepiercy]

We need an Administrator guide for Plone site admins, specifically how to navigate the control panels and install add-ons.

This should also implement the PLIP plone/Products.CMFPlone#3987 for screenshots, if possible.

We also need to reconcile this with #1768.

[Ipshita29]

hey @stevepiercy,, I’d love to work on this issue! Could you please assign it to me?

[stevepiercy]

@Ipshita29 no. You have not even bothered to review contributing guidelines, because you are asking to be assigned to an issue. Start there. Then after you have administered an actual Plone site, you can come back and do a thorough write up.

[davisagli]

@stevepiercy I'm a bit confused because in #1875 (comment) we discussed that we should merge the Admin Guide into the Developer Guide. But here you're talking about adding it to the User Guide. Are you talking about something else?

[stevepiercy]

@davisagli yes, sorry, I meant under the Admin Guide. Fixed.