Release v0.1.3 (swap ceil/floor with min/max, support for non-rectangular loops)

• Swap ceiling and floor function with max and min in target bounds computation
• Add support for non-rectangular loops (bounds must still be affine transformations of loop indexes and parameters)

For example, this starting loop is now supported:

FOR i FROM 0 TO N {
    FOR j FROM 1 TO i+2 {
        [loop body]
    }
}

v0.1.0

The very fist release of OPoly.