Add note about using released versions to README
Fix small typo in API docs
Small rewording in API docs
Add a bunch of 'not None' checks in method definitions

The 'key' and 'value' arguments to get(), put(), and so on cannot be
None. Enforce this using the function signature instead of relying on
error propagation when using string methods later on.
Avoid implicit package relative imports
Minor rewording in code comment
Remove unused variable
Add a Bitdeli badge to README
Add a Bitdeli badge to README
Drop extraneous newline in README
Add a a few arg type declarations and "not None" assertions
Inline _register_iterator() helper function

It's a one liner that is only called from a single place.
Support custom DB constructor kwargs in test helper
Support LRU cache sizes >= 2G by using correct integer type
Update NEWS
Let Cython create annotated HTML by default

This is useful for debugging/inspecting the generated code.
Make .seek() work correctly for PrefixedDB iterators

This fixes issue #15.
Explicitly initialize local variables in Iterator.current()

...otherwise Cython generates unnecessary UnboundLocalError checks,
even though these cannot ever happen with the current logic.
Expand PrefixedDB iterator tests
Bump version number to 0.5