Raise correct exception for duplicate networks

When using Quantum, if duplicate network ids are passed in on a
nova boot, nova-api raises a NetworkNotFound exception, which is
not correct.  This change causes it to raise a NetworkDuplicated
exception instead.

Fixes bug 1165088

Change-Id: I4f1f9aa5e1fa0e740b78e67760d924e2dd1d4d98
baremetal: Change input for sfdisk

To prevent sfdisk stopping with "bad input", use a empty string
instead of "-" (and doing so requires using "," as a separator).

Fixes bug 1166112

Change-Id: I5e4cffaa326fbafd1583d55744f921a40b3ae76f
Merge "Raise correct exception for duplicate networks"
Merge "baremetal: Change input for sfdisk"