A small patch to fix a few bugs in gtktext.c.
By Reed D. Meyer ([email protected]), 07/11/99.

     Fixes:
        * Bug in not properly displaying text after deleting selected text.
        * If an entire line of text is selected and deleted, the new-line
          is now also deleted (before, a CTRL-U wouldn't delete the \n).
        * The cursor now remains on the selected line after selecting a whole
          line.  Before, it would skip to the beginning of the next line.
        * Lines with exactly N characters (where N is the width of the text
          window), not including the \n, do not wrap.  Before, they did,
          which was annoying if you had text formatted to exactly the width
          of the text window (e.g., 80-char fields displayed on 80-char-wide
          windows wrapped).  A minor bug remains in that if you insert chars
          enough to make the line wrap and then delete chars with the cursor
          currently at the \n, the line won't unwrap until length gets down
          to N-1, not N, characters.  Too minor to bother fixing.