nm-initrd-generator scans the command line for options relevant to network
configuration and creates configuration files for an early instance of
NetworkManager run from the initial ramdisk during early boot.

Remainder of typos found using `codespell -q 3 --skip="./shared,./src/systemd,*.po" -I ../NetworkManager-word-whitelist.txt` whereby whitelist consists of:
 ```
ans
busses
cace
cna
conexant
crasher
iff
liftime
creat
nd
sav
technik
uint
```

https://github.com/NetworkManager/NetworkManager/pull/205

For now, the device only exposes partial link status (not including
peers). It cannot create new links.

Check that we don't repeat the omission in future.

This splits the manual into parts and groups the D-Bus interfaces into chapters
by the object class. It looks considerably better.