More type-safe way, instead of void* everywhere
void* instead of sal_Int8 for raw memory / multi-use buffers
Fixed more issues than I care to count, but at least:
 - updates to a DECIMAL were truncated to integer because DecimalDigits set to 0
   maybe/probably also NUMERIC
 - setObjectWithInfo(... DataType::LONGVARCHAR ...) was passed as AT_EXEC, but the buffer was already free()d by then -> crash or wrong data

Change-Id: I0e6791a05b96fb345bfe3f911386263e6cfedde9