Insert fillers between characters in a passed string
──────────────────────────────────────────────────────────────────────────────

 Syntax

        GT_StrExpand(<cStr>, [<nNum>], [<cChar>]) --> cRet

 Arguments:

      <cStr1>  - A character string to insert chars into
      <nNum>   - The number of fill characters to insert (default 1)
      <cChar>  - The fill chararacter (default space)

 Returns:

      cRet     - The input string with fill characters inserted between
                 every character in the original.

 Description:

      Inserts fill characters into a string.

      NOTE:
         invalid parameters will return ""

 Examples:


      ? gt_strexpand("abc")                    // prints "a b c"
      ? gt_strexpand("abc", 2)                 // prints "a  b  c"
      ? gt_strexpand("abc", 2, '■')            // prints "a■■b■■c"


 Source: STREXPAN.C

 Author:  Andy M Leighton