Navigation and screen title adjustments for Financial Batch UI

As part of integrating the 4.2 Batch Entry feature with the CiviAccounts financial batches - modify navigation and titles as follows:

1. Navigation menu changes

• add menu item to Contributions menu for "Financial Transaction Batches" (this item is not directly linked to a URL). This is a parent item for all the financial batch menu items. Place this below "Pledges".
• New Batch, Open Batches, Closed Batches, Exported Batches are children of "Financial Transaction Batches"

Nav menu will look like this after changes:
Contributions

• Dashboard
• Find Contributions
• New Contribution
• Bulk Data Entry (this is the renamed "Batches" entry from 4.2, we will update nav title in 4.2.3)
• Import
  =========
  Pledges ->
  =========
  Financial Transaction Batches ->
  New Batch
  Open Batches
  Closed Batches
  Exported Batches
  =========
  New Contribution Page
  etc.

2. Page titles for financial batches s/b updated to use the term "Financial Transaction Batch".