CSV Imports Overhaul (Transactions, Trades, Accounts, and Mint import support) (#1209)

* Remove stale 1.0 import logic and model

* Fresh start

* Checkpoint before removing nav

* First working prototype

* Add trade, account, and mint import flows

* Basic working version with tests

* System tests for each import type

* Clean up mappings flow

* Clean up PR, refactor stale code, tests

* Add back row validations

* Row validations

* Fix import job test

* Fix import navigation

* Fix mint import configuration form

* Currency preset for new accounts

test/controllers/import/configurations_controller_test.rb

@@ -0,0 +1,33 @@
+require "test_helper"
+
+class Import::ConfigurationsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    sign_in @user = users(:family_admin)
+    @import = imports(:transaction)
+  end
+
+  test "show" do
+    get import_configuration_url(@import)
+    assert_response :success
+  end
+
+  test "updating a valid configuration regenerates rows" do
+    TransactionImport.any_instance.expects(:generate_rows_from_csv).once
+
+    patch import_configuration_url(@import), params: {
+      import: {
+        date_col_label: "Date",
+        date_format: "%Y-%m-%d",
+        name_col_label: "Name",
+        category_col_label: "Category",
+        tags_col_label: "Tags",
+        amount_col_label: "Amount",
+        signage_convention: "inflows_positive",
+        account_col_label: "Account"
+      }
+    }
+
+    assert_redirected_to import_clean_url(@import)
+    assert_equal "Import configured successfully.", flash[:notice]
+  end
+end