Tracking integration for Depth Estimation

[osanseviero]

Tracking integration of task - Depth Estimation

Note that you're not expected to do all of the following steps. This PR helps track all the steps required to get a new task fully supported in the Hub 🔥

• Integration with Inference API. Select at least one of the following:
  • Added a transformers pipeline
  • Added to Community Inference API for 3rd party library
  • Added to Community Inference API for generic
• Added basic UI elements (icon, order specification, etc)
• Added a widget

Integration guide: https://hf.co/docs/hub/models-tasks

[sayakpaul]

@osanseviero I will work on it parallelly with a fine-tuning tutorial for depth estimation.