This commit resolves #232, resolves #264, resolves #268.

#232
- GoogleCloudService is restructured to support back-up action
- 'backup' : put all recording items into recordinSet(which is a set of archiving-approved-recordings)
- 'retry' : upload all items in the recordingSet.
- [recording-item ID] : upload the corresponding recording item.

#264
- During the recording is in progress, the screen is turned on continuously

#268
- when the access token is obtained, it is always validated by Google
- If the key is not valid, new token is issued and used.
- Previously used Google-account and Access-token are stored in Preference and used again without user's intervention next time.