Store additional parameters in EE db on WP site create

Following parameters are not stored during site create and I think should be stored.
```
proxy-cache-max-size
proxy-cache-max-time
version
dbcollate
dbcharset
dbprefix
```

These parameters will be needed for site clone in order to create a site identical with source(especially first two). Other parameters will also be helpful to recreate site or create an identical site at any point in future.