Add support of horizontal scrolling

[Stas-tolpekin]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report 
[x] Feature request
[ ] Documentation issue or request

Current behavior

The horizontal position of the target element is ignored by this library

Expected behavior

If the element has horizontal offset and placed outside of container viewport, horizontal scrolling should happen like vertical scrolling. If the element needs to be scrolled by both axes, horizontal and vertical scrolling should happen at the same time.

What is the motivation / use case for changing the behavior?

In my team, there are cases where we need to place html elements outside the viewport not only by vertical axis (Y). This feature can make this library useful in more use-cases. Right now it is usefully only for lists.

Environment

Angular version: 6+
Your version of `@nicky-lenaers/ngx-scroll-to`: 1.1.1

Browser:
All supported
 
For Tooling issues:
- Node version: 8.9.4
- Platform:  Windows 10

[r0manchak]

Hi!

Are there any updates regarding this issue?