Preparations for future updates
Fixed MVP voicing.

- MVP voicing now works for week, month and year
Add TriviaTime.getUsername().

- New method returns a user's registered username if it's a registered
  user or returns their nick if not
Updated Storage.getUser() and Storage.getUserRanks().

- Both methods now return dicts
- getUser() no longer appends the results of getUserRanks()
- Updated calls with new usage
- Added some comments for readability
- Renamed Storage.getUser() to Storage.getUserStat()
- Renamed Storage.getUserRanks() to Storage.getUserRank()
Added back a check in Game.checkAnswer().

- Added back a check to see if Storage.getUserStat() actually returns a
  non-empty dict, just in case
Small fix for TriviaTime.givepoints().

- Reverted functionality back to original state after breaking with the
  introduction of TriviaTime.getUsername()
- Still does not properly convert nick into username
Fixed small error in TriviaTime.handleVoice().

- Forgot to replace an instance of 'user' with 'stat'
Modified MVP voicing behaviour.

- MVP message will now only be shown if voice is given (ie. when there's
  no voiceTimeout for the user)
Fixed MVP voicing to voice by nick instead of username.

- Switched the actual voicing of players to use the player's nick
- Some small formatting changes
Improvements to readme; minor def changes

* Readme now includes information on which files to update from specific
versions to the current version.
Reduce streak bonus per #296

Reduces the streak bonus to half the question's point value, see #296
Added detail on editing tools to readme
Merge pull request #306 from tannn/testing

v1.06