Refactored vm monitoring code
Refactored vm monitoring code

Moved common code to functions to ease the addition of new vmi metrics.

Signed-off-by: Yuval Turgeman <f887c8e233fc33e29d147b00ac37d36619023210@redhat.com>

stu-gott/kubevirt,davidvossel/kubevirt,davidvossel/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,davidvossel/kubevirt,kubevirt/kubevirt,davidvossel/kubevirt,kubevirt/kubevirt,stu-gott/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt