Add 2D dimension

[mikhailmtion]

I have added the ability to take measurements in 2D. Toggler added, you can use it to switch to 2D measurement mode and get measurements at the top point.

Attached a screenshot

[mikhailmtion]

@aka-blackboots , Hi, for some reason, the Eslint check does not pass. In the main branch, the same problem

[agviegas]

Hi, all our efforts are now going towards this library, which will likely substitute both web-ifc-viewer and web-ifc-three. You can check the dimensions there, and feel free to open a PR if you think they need improvement!

[mikhailmtion]

@agviegas Hi! How is it better than web-ifc-viewer?

[agviegas]

Some of the reasons are:

• It's more modular & flexible
• It's much faster to load models
• It consumes way less memory
• Has better postprocessing
• It has way more tools (and all new tools are going to be here)
• It's going to be maintained in the long term
• The whole documentation + tutorials + testing is going to be release by the end of the summer