Auto distribute count for Intelligent Volume Provisioning

[aravindavk]

Current dynamic Volume create API accepts distribute count as input and defaults to 1 if no distribute count is specified. New feature is required to find distribute count automatically based on given Volume size and available size.

If Distribute count is not specified and disk space is not enough to create volume, try again with increased distribute count till all the bricks can be planned(till max distribute count)

[aravindavk]

Issue #851 is split into multiple issues. This is one among them

[aravindavk]

Alternate idea compared to Iterative method till max distribute count: New API tunable max-brick-size.

if (requested-size > max-brick-size) 
{
    distribution_count = int(requested-size / max-brick-size);
    if (requested-size % max-brick-size > 0)
    {
        distribution_count++;
    }
} 

[JohnStrunk]

I like the notion of having max-brick-size as it makes efficient bin packing easier when item size is constrained.