Merge pull request #295 from euanh/build-improvements

vhd-tool: Fix release number in changelog
Add -y switch to yum install

This way the install script does not require any user input.
Merge pull request #296 from matelakat/unattended-install-centos

Add -y switch to yum install
xcp-sm: Add udev rules and package dependencies needed to attach iSCSI volumes

Signed-off-by: Euan Harris <euan.harris@citrix.com>