Enable basic configuration of UI and indexing via config file

[acka47]

Possible things to be configured:

• Tokenizer, see Use "full" tokenizer for FlexSearch indexing #153 (comment)
• Reconcile server (see also discussion in SkoHub chat from 2022-04-01)
• Not relevant at the moment but when ActivityPub features are re-enabled: Enable inboxes, configure ActivityPub server to be used...

Questions:

• Should the config be made per repo or per vocab?
• What should the file look like? YAML?

[sroertgen]

Questions:

Should the config be mad per repo or per vocab?

Since a skohub-vocabs instance might host multiple vocabs I guess it makes sense to define this per vocab or give something like a default config if nothing is specified for a specific vocab. This might make implementation a little bit more difficult, but seems sensible.

What should the file look like? YAML?

I would actually favour TOML (https://toml.io/en/) over YAML, because it is easier to write and read for humans (easy for machines as well).

[sroertgen]

• UI should also be configurable

[sroertgen]

So to summarize the following options should be configurable:

tokenizer: see options https://github.com/nextapps-de/flexsearch/tree/0.6.32#tokenizer
ui:

• colors
• logo

And I think I will use yaml though I thought about using toml.

@acka47 Do you want the fonts to be configurable as well or are colors and logo sufficent?

[acka47]

Do you want the fonts to be configurable as well or are colors and logo sufficent?

Why not? As far as I can see, the only instance that customized the design (for test purposes) also adjusted the fonts: http://zpidvokabulare.surge.sh/index.de.html