Update README
Adding major, minor, patch version information to the *Config.h files.
Fix and test for re-reading deepscanlines

Attempting to read the same scanline multiple times would fail, leaving FrameBuffer sampleCountSlice unchanged
Fix makes subsequent reads copy data from the internal cache to the framebuffer for efficiency.
Test provided in IlmImfTest
Merge branch 'develop' of https://github.com/openexr/openexr into devel
Added PartHelper functions and test
Updated CompositeDeepScanLine to multithread compositing steps

DeepCompositing objects must now be threadsafe when readPixels decodes multiple scanlines and threading is enabled
Added support for setting view in exrmultipart
Added missing break statement