CRM-12764 : Add api for FinancialAccount and FinancialType

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* CRM-12764: Add API for FinancialType and FinancialAccount, perhaps for EntityFinancialAccount
  http://issues.civicrm.org/jira/browse/CRM-12764

Note: FinancialType and FinancialAccount are tested and working. EntityFinancialAccount is not fully working. 

Someone with more experience could check it out. I think that the issue is that the BAO is called CRM_Financial_BAO_FinancialTypeAccount and the DAO is called CRM_Financial_DAO_EntityFinancialAccount