Zero size Blob

[davidrapan]

https://github.com/accord-net/framework/blob/840aba6e077dee29c5978c6b697bcb56fae70f9d/Sources/Accord.Imaging/Blob%20Processing/BlobCounterBase.cs#L1304

Change it simply back or just handle zero size or + 1 at some point? Cause bounding box width of for example x1=1 and x2=1 should be 1, pixel is not zero sized.

(We reverted that change in our source version for now cause it's kinda don't match up now)

Regards, D.