add a macro to reduce method calls in api.py
fix #140. properly size char buffer for encryption
Unaligned block encryption test

This test verifies that the underlying buffer is being sized correctly
by passing data into the encryption function without aligning it to the
block size of the cipher. This ensures that we will get a larger return
value than the initial argument from our second encrypt call.
Merge pull request #141 from reaperhulk/block-cipher-buffer-sizing

Fix Block cipher buffer sizing