Add ability to disable panning in the OrbitManipulator

[mentholyspirit]

It's useful when you want to have the ability to rotate the camera, but want to limit panning.

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[mentholyspirit]

@pixelflinger The problem then comes when someone tries to use it like this: Config config = {}; config.upVector = vec2(1.f, 0.f); mainpulator.setProperties(config) Then panning will be set to false, which is not the expected behaviour.

[pixelflinger]

@pixelflinger The problem then comes when someone tries to use it like this: Config config = {}; config.upVector = vec2(1.f, 0.f); mainpulator.setProperties(config) Then panning will be set to false, which is not the expected behaviour.

Why can't we set panning to true by default in Config?

[pixelflinger]

@mentholyspirit the Android presubmit is failing.