Hbase client

The most contentious part of this is the non-strict inequality on line 68. `simhash-db-py` uses non-strict inequalities for redis and HBase, but strict ones for Riak and MongoDB.
It looks like `happybase` supports the ability to send multiple cells at once for a given row key, which will almost certainly cut down on overhead:

```python
for hsh in hashes:
    row_key = struct.pack(...)
    cells = dict((column_name(i), None) for i in range(self.num_tables))
    self.table.put(row_key, cells)
```