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Fix bug #2790076; running a procedure that has only empty body lines no longer crashes. This is a variant of a bug that was fixed a long time ago, but it appears as if the fix only works if the procedure is run once. After digging into the code, I think this is because the evaluator assumes that that if is_tree(node) is non-zero, then treepair__tree(node) will be non-NIL. This assumption is violated when a body list consisted of entirely empty lines was treeified. The previous (inadequate) fix was to add some logic to remove this assumption from the evaluator. The new fix is to simply not flag these degenerate functions as being treeified. This causes the evaluator to fail-out, instead of trying to run a procedure with no meaningful body. This seems to work, but all changes to the evaluator are risky and can cause subtle regressions.

Cleanup: Remove unparsed__tree() and tree__line() which were never used and whose definitions were confusing.

Add a regression test for bug #2790076, which is an AV when running a procedure that is created with DEFINE and consists of nothing by empty lines.

Implement request #2789706; Helper procedures for SORT now begin with ".fmslogo.sort." so that they don't clash with names in Erich Neuwirth's sorting library. (His library has a procedure called "sort.merge" which resulted in very strange behavior when "SORT" was loaded).

Move the "Special Thanks" section to the release notes. The list was growing very long and made it less likely that users would see the semi-actionable information within the file.

Add support for matching braces to the paren matching logic.

Remove TMiniEditor::CmSelectAll(). As far as I can tell, TDialog doesn't use accelerators, so this was never called. Anyway, CTRL+A and "Select All" from the context menu still work without this, so it wasn't necessary.

Add some rudimentary support for paren matching. This is accessible through CTRL+].

Fix typo in comment.

Rename a local variable, fix whitespace.