forcing version of is-url

[gmarkv10]

Description

I have taken off the ~ character for your is-url dependency. They pushed an update for the first time in two years and it broke parsing when passing in an HTML string as the first argument to an x-ray function. This forces the version of that dependency to the last stable commit.

Checklist

• [x] Code compiles correctly
• [x] Created tests which fail without the change (if possible)
• [x] All tests passing
• [x] Extended the README / documentation, if necessary
• [ ] Added myself / the copyright holder to the AUTHORS file

[lathropd]

Not seeing the reported issue. Seems to have been otherwise resolved.