change currency three-letter-code to DOGE

also change length of currency amounts in UI

(cherry picked from commit inutoshi/inutoshi@8dcef8791a02327c8061235df7a77e2da6b59ee2)
Updated port numbers to reflect Dogecoin port numbers.
Replaced simple references to Bitcoin, with Dogecoin.
Correct naming of application and packages from Bitcoin to Dogecoin.
Replace Bitcoin reference and old version with Dogecoin in Doxyfil.
Completed replacement of Bitcoin with Dogecoin in core documentation.
Replaced port number references with Dogecoin ports.
Replaced simple references to "Bitcoin Core" with "Dogecoin Core"
Reworked English and French language translations to reflect Dogecoin instead of Bitcoin.
Merge pull request #364 from rnicoll/1.7-dev

Rework documentation and English and French translations to refer to Dogecoin
Merge pull request #363 from leofidus/1.7-currencyname

1.7: change currency three-letter-code to DOGE
Update bitcoinunits.cpp

Adding a name for the smallest possible unit. :>
Update bitcoinunits.cpp
Update bitcoinunits.h

Adding Koinu @leofidus :D