Document kramdown abbreviation syntax in handbook
As documented in #4762, usability of acronyms is limited when the definition is made in place on a long document. Kramdown already supports a lightweight markup for abbreviations but it is fairly opaque to the user.
Proposal
Update the handbook to include specific usage of the Kramdown abbreviation syntax until we can build a more automated solution as recommended in #4762
Edited by Eric Schurter