force deep clone of lab_interactive_template

In Ruby Hash.clone is a shallow clone on Linux while
it appears to be a deep clone in Mac OS X. Avoid this
problem by using Marshal.load( Marshal.dump(hash)).
Change 'timestep' to 'timeStep' in converted E2D models

Previously it was changed in only the implementation.
Simplify boundary conditions definition in Energy2D converted models
Use new structure of boundary conditions in Energy2D
Let user dynamically adjust options of Energy2D simulation

51873425

=> Do not store them in closure variables. Each time when some option
is needed, read it from properties object provided to engine /
solvers. The only exception is for immutable options, which can be
stored in closure variables for convenience.
Fix sun angle slider template for Energy2D interactives

Use radians.
Update Energy2D visualization when view option changes

51873425
Save imported Energy2D interactives in energy2d/imported subdir
Move all auto-generated Energy2D interactives to right directory
reference new location: imported energy2d interactive
Update generated Energy2D Interactives