Add an Infinite Canvas / Wraparound mode for Krita

by Shrikrishna Holla for KDE

Krita focuses on texturing, matte painting and comics drawing. For texturing, the Krita image model needs to be expanded in two ways: First, the canvas needs to be made infinite, so the user can paint textures of any size without stopping, and second, a mode for creating tileable textures where painting strokes that go off the canvas, wrap over on the opposite side avoiding texture seams along the edges. Panning in this mode would essentially work just as an offset for the whole canvas to wrap around, allowing artists to check tiled textures for seams.