Existing metric as a template for a new one

### User story
Given existing metric `A` with many tags.  Want to create new metric `B` which will have the same tags as `A`, but with some changes.

Currently I have to type all the tags for `B` manually.

### Desired solution
A button on metric `A` like `New metric from this one` which will create new metric `B` with tags from `A`.

Probably it depends on #194.