v8.1.2

Bug fixes mostly (compared to v8.0.0):

• use int64_t, to ensure 64-bit ints are 64-bit on all platforms
• add guards to some kernels to prevent crashing on certain geometries
• python build works on OS X now
• fixed some OpenCL warnings, and some failing tests
• python build works now when opencl headers not present

Also, one minor feature-ette:

• in python, can call 'getLabels' on a SoftMax layer

Native library downloads (for linux and Windows; Mac you need to build your own for now...):

• http://deepcl.hughperkins.com/Downloads/
• usage instructions in the readme, https://github.com/hughperkins/DeepCL