[FEATURE] Cryptocurrency daemons monitoring via notification providers
**Is your feature request related to a problem? Please describe.**
Sometimes daemons (or their RPCs) are faulty, and the only way to know about such events is from angry customers or when opening bitcart admin UI. Although it is rare event, when it happens, it is pretty inconvenient.

**Describe the solution you'd like**
I would offer implementing feature making use of configured "notification providers" at the admin UI to notify instance administrators of an issue detected as soon as possible.

**Describe alternatives you've considered**
It is possible to use `bitcart-cli.sh` and custom shell-scripts to implement it, however it will be pretty messy and I consider this feature as worthy to be upstreamed.

**Additional context**
N/A
