prepare skeleton code for IndexWriter
refactor Codec; implement IndexWriterConfig constructor
manually set default similarity
add NoOutput; add TieredMergePolicy constructor
add NoOutput; add TieredMergePolicy constructor
add DocumentsWriterPerThreadPool constructor
re-arrange test logic
implement TestRuleSetupBeforeAndRestoreClassEnv.before()
workaround Lucene Java's SPI mechanism
refactor Codec as interface
refactor Codec as interface - fix unit test
prefer Go friendly property names
add RandomSimilarityProvider skeleton code