Re-structured coin config options section.
* Replaced acceptFirstOput with useDefaultAccount parameter.
* Moved blockTemplateModeRequired and txMessageSupported to main section.
Removed unused BlockTemplateOptions, GenTxOptions,
Fixed coin configs.
FindPoolAccount() on BlockProcessor.cs, PaymentProcessor.cs and ShareManager.cs now sets the pool account based on useDefaultAccount from coin-config.
Fixed back Transaction.cs:GetPoolOutput().