Bug fixes based on test failures. Firstly, make sure that the Epub only attempts to clean up
the unzipped epub archive when there actually *is* an epub archive (i.e. it hasn't been loaded
from sql). Secondly, make sure that the hash value is stored and retrieved from the database as
a 64 bit integer.
Changed the encoding, otherwise there's a horrendous segfault. Thankfully it's not in my code.
First part of this test case, testing the loading of just the Epub members.