engine: OS type validation

This change displays an error if the selected operating system of the
VM or Template is not compatible with its architecture.

Change-Id: I2ff3fbada65e72e6fbb944cb56fb35d5acc88a89
Signed-off-by: Gustavo Pedrosa <gustavo.pedrosa@eldorado.org.br>
Signed-off-by: Vitor de Lima <vitor.lima@eldorado.org.br>