Add feature to disable bounds for zoom, closes #33

[renekorss]

Useful if bounds are set to hold content in container.

Fixes issue with options like:

{
    bounds: true,
    boundsPadding: 1,
    boundsDisabledForZoom: true
}

This will hold content inside container (not being able to pan out of container) but zoom would still be useable.

[miksansegundo]

This PR is working very well. Would love to see it merged and released👍

[hirbod]

This PR is awesome and should be integrated.

[zakariafadili]

it is an interesting option, plan to integrate it?

[lilletech]

it is an interesting option, plan to integrate it?
I'm waiting for it too !!!!

[i-chirkov]

Any info about PR to be merged?

[davidmarogy]

I have the issue in my angular project, that if i set bounds to true and boundspadding to 1, that it is not possible anymore to zoom.. Is there also a functionality for typescript so that it is possible to zoom while having bounds: true and boundsPadding:1? Like the above " boundsDisabledForZoom: true"?