v0.1.0a14: Fix up `blocks_split`.

• No longer erroneously removes blocks.
• Computes the halo relative to each block for easy removal.
• Returns both the blocks to compute and the halos to trim off each block.

v0.1.0a13: Added better support for blocking and improved/extending CI support

• Add new function blocks_split.
• Improved Travis CI testing.
• Added support for testing with Wercker CI.