Ability to generate multiple short URLs from the same long URL

When submitting the same long URL twice, Shurly returns the same non-custom short URL.

It would be nice to add a feature which gives the following options:

• List the existing Short URLs so they can be re-used
• Allows to generate a new short URL for an existing long URL

This feature would be useful for tracking purposes, for example, different short URLs could be used in different marketing campaigns.