Change URL to match new FileStack domain

[azranel]

This is just small change to adjust to most new FileStack domain. Nothing fancy. 😄

[coveralls]

Coverage remained the same at 100.0% when pulling 2239b4a on azranel:change-url into c26b2d8 on Ink:master.

[maurogeorge]

Hi @azranel thanks for the PR.

Could you please update CHANGELOG.md with a brief description of your changes under the unreleased heading.

And please take a look at the specs they are broken in this PR.

Thanks a lot

[maurogeorge]

@Ink/ruby-developers In this patch is change the JavaScript file, it is the same JS file of the version 2 is a new one?

Do you think we will need to update the gem version to v3, as we did here 1.

Thanks

[kyuss]

👍