Moved part of main logic to a method.
Fixed bad variable name.
Introduced memoization for file's crc32.
Readjusted file structure and added gemspec.
Major structure reshuffling.
Fixed compilation issue.
Got rid of build warnings.
Extension is compilible now.
C Sources are correctly built now.
Rake is development requirement.
Achieved working state.
Updated documentation.
Merge pull request #20 from tdobrovolskij/refactoring

Refactoring. Complete restructuring.