tabular parser doc revision 1
Hi @mscheidg, @sbrueck I started this MR from the need of some extensions of tabular parser documentation by @amgo.
I will try to shape it as an HowTo and move elsewhere the parts that go beyond an HowTo purpose.
An overarching Tutorial issue #1653 (closed) is being opened by @hnaesstroem that will reference this HowTo.
A cascade of side info will probably fall in Learn within this MR, too.