Fix kwargs for FloatingIPPortAlreadyAssociated.

Updates the NVP plugin to use the correct kwargs when raising
l3.FloatingIPPortAlreadyAssociated.

Fixes LP Bug #1159922.

Change-Id: If89feea5e40976ccb4286f96f5348c54f84950ce
Fix kwargs for NECDBException.

Updates the NEC plugin to use the correct kwargs when raising
NECDBException.

Fixes LP Bug #1159925.

Change-Id: I1e96d4ec65c1bc98d90d2eb9867fe39bbd505cdc
Merge "Fix kwargs for FloatingIPPortAlreadyAssociated."
Merge "Fix kwargs for NECDBException."