Update version for NC32 compatibility

[notapirate]

Add NC32 support

I went through the migration guide at https://docs.nextcloud.com/server/stable/developer_manual/app_publishing_maintenance/app_upgrade_guide/upgrade_to_32.html --> app is not affected

I tested the app with NC32 --> successfully

Closes #169
Closes #170

[punk-t]

Confirmed for me (NC32.0.1)
As a hint: I had to reconfigure Unsplash API token
As another hint: NC config page requests a 'token' to use Unsplash API. This is kind of misleading, as Unsplash generates an 'access key' (that is used as the 'token' in NC) and a 'secret key'. Both are confidential, neither of them refers to a 'token'.

[roliverio]

Can this be merged?. thanks.

[notapirate]

Can this be merged?. thanks.

Absolutely, I think many users are waiting for this update

[ArjonBu]

What's stopping this from being merged?

[Kev600]

After updating my NC AIO to 32 - I needed to go back to the Splash app and 'allow untested app' - Then 'Enable' it again - It retained my key and worked right away! (please move this comment if it's in the wrong place!)