Add view control gui plugin and support orthographic view

[iche033]

Summary

depends on gazebosim/gz-rendering#322

• Updated view controller in Scene3d to support both orbit and orthographic view controller
• Added View Control gui plugin that makes service request to Scene3D to toggle between the two view controllers

I can port the changes here to ign-gui if it helps in merging the two Scene3D classes.

To Test

Run ign-gazebo, open the GUI plugin menu (3 dots on top right) and select View Control plugin. Choose Orthographic from the drop down list to see the new view controller.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

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[chapulina]

I can port the changes here to ign-gui if it helps in merging the two Scene3D classes.

Thanks, yeah that will help. The current plan is to deprecate GzScene3D in Fortress (gazebosim/gz-gui#137).

[nkoenig]

Can you add ortho/perspsection control to the ViewAngle plugin instead of creating a new plugin?

[iche033]

Can you add ortho/perspsection control to the ViewAngle plugin instead of creating a new plugin?

done, merged. 7218ef2

[iche033]

The test failures look unrelated: level_manager, depth camera test, etc since the changes in this PR are limited to 2 GUI plugins. I think this is good to merge.