TDbf 6.4.8 released

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V6.4.8

- remove duplicate names, may cause ambiguity
- allow duplicate names in function list for expressions
- remember exprword reference for every field variable so we can remove it
- prevent possible buffer overrun when parsing expression (thx leexgone)
- fix some memory references in the parser
- add ability for locate/lookup to use alternate index than current one
- fix tdbf.copyfrom fieldname copy and fieldno index for size/precision
- make TDbf.CheckMasterRange public so master/detail can be synced manually
when for example .DisableControls is active
- allow calc/lookup fields to work in filters
- fix loosing blobs when packing table (rep by cllerici)
- support variants for freepascal
- fix (filter) parser string partial matching for "A*" strings
- make distinct index creation more robust