ability to specify slower speed transition

[kfarr]

as a user making a presentation or video from my 3dstreet scene, i'd like to slow down the transition speed for the double-click-to-center feature

workaround:
in EditorControls.js manually edit line 96
scope.transitionSpeed = 0.00025;

(note that changing line 111 does not have any effect since it is presumably set in 96)

ui considerations - where to put this? some ideas:

• in the toolbar, a toggle between immediate (lightning / no transition), fast (rabbit / current behavior), and slow (turtle) the latter two similar to dji drone speeds
• as a property in a component on the Viewer layer (perhaps as part of converting this transition animation from a fakeComponent to a real component) -- advantage, no new UI is needed, simply let user set a value

[vincentfretin]

Oh, that's a leftover during my tests. The line 96 should be removed really, and keep only line 111.

[vincentfretin]

I'll keep that need in mind when rewriting that code to a real component on a real entity for the Viewer layer in #851 probably use the following schema
{name: 'speed', oneOf: ['immediate', 'fast', 'slow'], default: 'fast' }