LT-14999: Fix mismatched Paragraph tags

Remove check for FlowType before checking for invalid configuration.
Call virtual Open- and CloseParagraph methods from non-virtual
Open*Para and Open- and CloseInnerPile, so tags are actually written.
Reorder XmlVc methods for better readability.

Change-Id: I835af1b48ea00c73bc16feff52a4fc4ea1183e5b