Merge pull request #18 from glebm/highlight-docs

Highlight Readme syntax
Merge pull request #14 from glebm/batch-pool

Translate in batches
Updates README and added note on concurrency [#14]
should_receive instead of stub!
Merge pull request #19 from glebm/refactor-require

Refactor require
Bump version to 0.4.0
require version using absolute path in gemspec