FT_AADDITION()
 Add elements unique of source array to target array

 Syntax

      FT_AADDITION( <aList1>, <aList2> [, <lTrimmer> [, <lCaseSens> ] ] ) ;
              -> aNewArray

 Arguments

     <aList1> is the primary array.

     <aList2> is the secondary array.

     <lTrimmer> is a logical value denoting whether leading or
             trailing spaces should be included in the
             comparison. If .T., then ignores spaces in
             comparison, defaults to .T., .F. includes spaces.

     <lCaseSens> is a logical value denoting case sensitivity.
             If .T., then comparison is sensitive to case,
             defaults to .T., .F. ignores case.

 Returns

     An array of the union of aList1 and aList2.

 Description

     This function will add the elements unique of aList2 with aList1.
     It returns a new array including all the elements of aList1
     plus the unique elements of aList2.

 Examples

     aList1 := {"apple", "orange", "pear"}
     aList2 := {"apple ", "banana", "PEAR"}

     FT_AADDITION( aList1, aList2 )
          // ignores spaces, sensitive to case
          // returns {"apple","orange","pear","banana","PEAR"}

     FT_AADDITION( aList1, aList2, , .F. )
          // ignores spaces, not sensitive to case
          // returns {"apple","orange","pear","banana"}

     FT_AADDITION( aList1, aList2, .F., .F. )
          // sensitive to spaces, not sensitive to case
          // returns {"apple","orange","pear","apple ","banana"}

 Source: AADING.PRG

 Author: Ralph Oliver,  TRANSCOM SYSTEMS