**Summary**
Add VPP coredumps.
In order to debug a crash of VPP, it is required to provide a coredump file, which allows backtracing of the VPP issue.
Add this option configurable.
**Use case**
Collect debug information
**Additional information**
https://fdio-vpp.readthedocs.io/en/latest/usecases/contiv/CORE_FILES.html
Proposed CLI
```
set vpp settings unix coredump
```
Additional packages: `gdb, vpp-dbg`