Created entities Transaction and Subtransaction

Created relationship between Transaction and Subtransaction, and between Account and Subtransaction.
Created Transaction controller
Created Transaction form
Reordered showAction and newAction because newAction was being overridden.

Also added @Method("GET") to newAction.
Renamed Subtransaction to LineItem.

LineItem seemed to make better sense for the business model, and more intuitive for users.
Added name for route newAction
Created form for new transaction.

The form is still under development, but so far you can add new LineItem rows.
Installed FOSJsRoutingBundle
Added type field to Line Item form
Separated javascript into separate file.
Created entities Payee and Payer

These are basically the same, but Payee is used for expense transactions,
      while Payer is used for income transactions.
Created entity Budget
Created entities MasterCategory and Category
Added relationships to BudgetCategory entity

Also generated migrations to match these entities.
Added payee field to LineItem form
Allowed payers to be selected when income is chosen as transaction type
Allowed payees to be selected in new transaction

When expense or transfer is selected as transaction type, then the
Payer/Payee dropdown will be populated with payees.

See commit b0077981be350a027d4accc071e3e3bb728a87ec for the equivalent when
income is selected.
Renamed payersGetListAjaxAction to listAjaxAction
Allowed type to be selected in added rows

When a line item is added, type can be selected, which will affect the
Payer/Payee dropdown.

see commits b0077981be350a027d4accc071e3e3bb728a87ec and
115f537afbaeeac2d86c6a042e23a87163d53a63 for more information.
Removed parameter `e` from updateType because it isn't needed