debug logging message with string encoding.
added ascii-only flag to logging message.
encoding check at internal utility function.
saved message data encoding is ASCII-8BIT.
encoding of message data at fetch command response is changed.
protocol decoder. renamed class name from `RIMS::ProtocolDecoder' to `RIMS::Protocol::Decoder'.
mail store message API. added read only folder open method.
protocol decoder. refactored select command.
protocol decoder. implemented examine command.
protocol decoder. defined DSL for unit test. command test cases are formatted.
protocol decoder. defined DSL for unit test. command loop test cases are formatted.
code format.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_append'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_expunge'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_fetch'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_store'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_store_silent'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_uid_store'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_uid_store_silent'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_copy'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_uid_copy'.
protocol decoder. refactored `RIMS::Test::ProtocolDecoderTest#test_command_loop_create'.