Add 'vdi-similar-content'

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Add vdi-compose

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Update ChangeLog

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #2 from djs55/similar-content

Add vdi-similar-content and vdi-compose
Merge branch 'master' of github.com:xapi-project/sm-cli

Signed-off-by: David Scott <dave.scott@eu.citrix.com>

Conflicts:
	main.ml
Update ChangeLog

Signed-off-by: David Scott <dave.scott@eu.citrix.com>