This commit resolves #244, resolves #257, and is related to #245, #84

#257
- bug is resolved
- Codes showing recording-items are now moved from ListenActivity and ListenRespeakingActivity to RecordingArrayAdapter.
  (Unnecessary codes in the two activities are removed)
- <include ,,> -> <listview ..> so all recording-related information is shown by RecordingArrayAdapter functions

#245
- Search-interface is supported in the menu
- RecordingArrayAdapter supports filtering of recording-items by language-code
- Recording-items at the front-page are dynamically filtered by language-code typed in search-interface.

#84
- issue84(a branch for transcript-support) is now merged
- transcript file-name format is (first speaker ID)-(8digit)-transcript.xxx
- transcript file format is (start time)\t(end time)\t(speaker)\t(transcript)[\t(translation)]
- currently, there is only one-to-one relationship between transcript file and original-wave-file.
Remove this too since we can get it back from git history if needed.