Japanese v2.3

Just uploaded for review. Available in a few days. Summary:

[New] Completely rewritten example sentences module. Sentences are broken down into vocabulary which can, themselves, be searched or added to the current deck.
[New] When showing words, the component kanjis are shown in "1 sticky" view.
[New] New stats at the bottom of each sticky.
[New] "Safe Start" option in device settings in case of startup problems.
[New] Delete option when editing a sticky.
[New] "Report mistake" (to me) option when editing a sticky.
[New] Tab bar icons.
[New] "Make current browse options the default" (for all decks) option.
[New] 1 second startup time on iPhone 4s.

[Fixed] Corrections to N1 (file needs to be reset to see changes)
[Fixed] Dropbox backup now backs up stats correctly.

27 minor changes/optimisations (大変でした). Bugs fixed.

Next update: Dictionary.