Prepare 3.2.0

[julien-nc]

Added

• Admin setting to choose transcription model @julien-nc #154
• Admin setting to set the default image size @julien-nc #135
• Add ability to customize API root path in service URL @edward-ly #143

Changed

• Encrypt api keys and basic passwords for app config and user settings @julien-nc #136 #139
• Remove old providers since old APIs can use TaskProcessing providers @julien-nc #140
• Cache the models for 30min in distributed cache @julien-nc #152

Fixed

• Missuse of user ID in most providers @julien-nc #153
• Use api key in image retrieval request @julien-nc #147