Pxc 4469 sst clone

[Tusamarco]

Adding preview POC for the Clone method for SST.
The script is based on the one from codership but then need to refactor almost in full to have it working with PXC.
birdeye flow

#              ┌──────────────────┐                      
#              │  Joiner starts   │                      
#              └────────┬─────────┘                      
#              ┌────────▼─────────┐                      
#              │open NetCat listnr│                      
#              └────────┬─────────┘                      
#              ┌────────▼─────────┐                      
#              │Send message to Dn│                      
#              └────────┬─────────┘                      
#              ┌────────▼─────────┐                      
#              │Donor decide IST  │                      
#              │or SST. Send msg  │                      
#              │through NC and    │                      
#              │waits for Joiner  │                      
#              │Clone instance    │                      
#              └────────┬─────────┘                      
#              ┌────────▼─────────┐                      
#              │Joiner get IST    │                      
#              │or SST.If IST     │                      
#              │Bypass all and    │                      
#              │Wait for IST.     │                      
#              │SST Start clone   │                      
#              │Instance and wait │                      
#              │for donor to clone│                      
#              └─────────┬────────┘                      
#              ┌─────────▼─────────────┐                 
#              │Clone process is       │                 
#              │reported.              │                 
#              │When done Dn waits     │                 
#              │Joiner close instance  │                 
#              │And performs 3 restarts│                 
#              └──────────┬────────────┘                 
#              ┌──────────▼──────────────┐               
#              │1) To fix dictionary     │               
#              │2) To recover position   │               
#              │3) Final cleanup         │               
#              └──────────┬──────────────┘               
#              ┌──────────▼──────────────┐               
#              │Send final ready signal  │               
#              │Waits for IST            │               
#              └─────────────────────────┘               

[it-percona-cla]

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[Tusamarco]

I have a question...
the two file wsrep_clone and wsrep_common_clone are not copied over when I do make install where is that defined?
@kamil-holubicki @venkatesh-prasad-v