TDbf 6.4.2 released

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V6.4.2

- fixed: overflow in storing float field data (large negative number) (thx madruga)
- fixed: restructure/pack create MDX database desktop compatible;
write db filename in mdx header (rep by rusmonk)
- fixed: freepascal objfpc mode compatibility fixes (still needs some @-ies)
- fixed: upon TDbf.Delete, use internal editing/posting such that BeforeEdit
and other events are not fired; also fixes cursor position bug upon
deletion (rep by bura)
- fixed: only use float fields (UseFloatFields) if int64 not supported
- fixed: deleted records undeleted when using RestructureTable with
Pack=false (rep by scenes)
- fixed: made (hopefully) all references to units lowercase, for kylix