Refactor meshes: buffer geometry + remove physics

[sasha240100]

As I described here, we should:

• Remove the use of params.softbody.
• Use BufferGeometry().from() in meshes that don't support buffer geometry yet.

I think ExtrudeBufferGeometry was added in latest three.js dev version.

Version:

• v2.x.x
• v1.x.x

Issue type:

• Bug
• Proposal/Enhancement
• Question
• Discussion

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Tested on:

Desktop

• Chrome
• Chrome Canary
• Chrome dev-channel
• Firefox
• Opera
• Microsoft IE
• Microsoft Edge

Android

• Chrome
• Firefox
• Opera

IOS

• Chrome
• Firefox
• Opera