You can call ubuntu-device-flash with --size less than 4

[Leo Arias]

$ ubuntu-device-flash core -h says:

-s, --size= Size of image file to create in GB (min 4) (4) help says:

But I can call it with a size of 3. So either the help is incorrect, or we need to raise an error when the command is called with a size less than 4.

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: ubuntu-device-flash 0.20-0ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-15.15-generic 3.19.3
Uname: Linux 3.19.0-15-generic x86_64
ApportVersion: 2.17.2-0ubuntu1.1
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Jun 3 10:13:38 2015
EcryptfsInUse: Yes
InstallationDate: Installed on 2015-05-25 (8 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
SourcePackage: goget-ubuntu-touch
UpgradeStatus: No upgrade log present (probably fresh install)