Fix cnn and add SatCLIP

[gabrieletijunaityte]

What does this PR do?

This PR is on top of #106

• Adds SatCLIP coordinate encoder.
• Fixes CNN:
  • Trainable layers are appropriately passed on in the setup() method. (Issue CNN trainable layers #64)
  • Moves out model freezing from CNN encoder to the BaseModel.

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[vdplasthijs]

Let's merge #106 first (before I review/merge), then update the branch of this PR, so the file changes don't duplicate what is in #106.

[vdplasthijs]

Great work. I think the use of freezing_strategy in config files (and elsewhere?) needs to be removed, and was just wondering where freezing happens now? Thanks!!