Support column headings in JIRA Issues Macro

Problem Definition

Currently JIRA Issues macro only allows for row headings, that is, the headings are all on the top row.

Suggested Solution

We should provide a way that customers can switch to the first column as a heading instead, should they so chose

Why this is important

We already offer the way to switch headings in our table macros, so we should allow the customers to use the same formatting for their JIRA Issues Macros