Add "duplicate" option to Custom Entities

[proddy]

As requested by JHa on Discord

I also would like to suggest about an enhancement request: Wouldn't it be helpful to have something like "duplicate" on existing entities. Often you just want to change the offset of an already existing entry and a duplicate would help to enter nearly same entities more easy. Just as an new idea

[proddy]

We'll see how much effort this is. One quick way is to export the Custom Entities and edit the JSON file using a text editor and re-importing it back into EMS-ESP. It's always good to keep a backup of the files.

[gh47110815]

Hey what a surprise ;-) - I just checked for updates, saw #2266 in the release notes, installed 3.7.2-dev.4 and ..... I was deeply impressed.
Duplicate entry works - very cool - THANK YOU very very much.

[proddy]

👍🏻 That was all Michael's great work