Add theming information to capabilities for the client

[nickvergessen]

Usefull for nextcloud/android#240

@AndyScherzinger@rullzer@MorrisJobke@schiessle

While this is an enhancement I would favor a backport, so the android app can use the name in 9 and 10 as well instead of having a useless "Nextcloud" in the title bar, to identfy the accounts. @karlitschek

[mention-bot]

@nickvergessen, thanks for your PR! By analyzing the annotation information on this pull request, we identified @LukasReschke, @schiessle and @juliushaertl to be potential reviewers

[nickvergessen]

While backporting this needs to be made php 5.4 compatible

[juliusknorr]

This is partly what #885 describes, right? Haven't looked into what capabilities exactly provide.

Shouldn't we also add the background image and logo if they are set?

[AndyScherzinger]

@juliushaertl for theming information completeness yes, even though the server name and the graphics and colors are different issues client-feature-wise.

[nickvergessen]

Okay, well when we add the images (URLs? or full file?) then I guess a new route is better

[LukasReschke]

Okay, well when we add the images (URLs? or full file?) then I guess a new route is better

URL seems more flexible.

[juliusknorr]

@nickvergessen

ThemingDefaults::getLogo and ThemingDefaults::getBackground can be used there, they also return the URL for the default images if there are no custom ones set.

[karlitschek]

Easy enough that a backport makes sense 👍

[nickvergessen]

Added the image URLs and tests

[MorrisJobke]

Tested and works 👍

[rullzer]

LGTM