Add: finance_transaction_editor_set_type, finance_transaction_editor_get_type methods and  PROP_TYPE propet as a enum

Add: PROP_TYPE property and finance_summary_child_get_type, finance_summary_child_set_type methods and documentation.

Create: finance_transaction_row_get_type and finance_transaction_row_set_type methods, PROP_TYPE property

Change: CONTROLLER_TRANSACTIONS to TRANSACTION_VIEW_CONTROLLER

See merge request !1

Change: finance_editor_get_date and finance_editor_get_frequency_date methods return a GDateTime, PROP_DATE and PROP_FREQUENCY_DATE as a GDateTime

Removed: color variable,  property  PROP_COLOR, create_icon, dispose class, finance_summary_child_get_icon, finance_summary_set_icon methods. Changed: finance_summary_child_get_icon to finance_summary_get_icon_name, finance_summary_child_set_icon to finance_summary_child_set_icon_name and icon variable to icon_name.

Removed: finance_summary_child_get_color and finance_summary_child_set_color methods. Changed: finance_summary_child_get_icon to finance_summary_child_get_icon_name and finance_summary_child_set_icon to finance_summary_child_set_icon_name.

Change: finance_transaction_row_get_color to finance_transaction_row_get_icon_color, finance_transaction_row_set_color to finance_transaction_row_set_icon_color, finance_transaction_row_get_icon to finance_transaction_row_get_icon_text, finance_transaction_row_set_icon to finance_transaction_row_set_icon_text, icon variable to icon_text and color variable to icon_color