Move code to convert SATOSHI/WHOLE into the TradeFormController to prevent duplication, remove usage of Big() in SendAssetsController in favor of conversion within the template via convertSatoshiToDisplayedValue.
Modify template modal for sale page to use convertSatoshiToDisplayedValue and getDisplayedAbbreviation. Modify template for sale page to use BTC instead of mBTC, and getDisplayedAbbreviation. Additional modifications and smart selection of placeholder values based on coin divisibility. Supporting controller changes mimic those from the send page, with slight modifications to fit the sell page logic. Removal of millibit references in Controller.