v0.12.1 - Default url bug fix

What's Changed

• Remove arc(ing) by @sansyrox in #156
• Fix: default url param in app.start by @sansyrox in #160

Full Changelog: v0.12.0...v0.12.1

There was an error in the previous release that the app.start() function was defaulting to 128.0.0.1 instead of 127.0.0.1. This PR fixes it.

This release fixes it.