Resize integral / ranges and create integral / ranges

[lpatiny]

There is currently an issue if you would like to create 2 integrals or ranges that are next to each other.

If you try to create the second one, you end up resizing the first one rather than adding a new one, and this is quite frustrating.

I would suggest that:

• If shift is pressed, you always add a new integral or range.
• If shift is not pressed, you either zoom or resize the integral/range if you touch the side of an integral/range.