= <,> command
        .shift out the space on the top/end of line.
         shift to the left/right max n byte until space char on the
         top/end of line exausted.
        .for margined file,only data in the margin is shifted.
        .n of x[n],xx-xx[n] is shift count,default is same as tab count.
         tab count is set by TAB command and default is 4.
         xn,b.s pattern is not supported.
         effect of b,s parameter is same as "(" command.

        .space shift out

            <<     |1234567890ABCDEFG
            0002000|      7890ABCDEFG
            <<     |   4567      DEFG
            >>     |1234567890A
            0005000|12   678
            0006000|  34567890ABC
            >>     |1234567890ABCDEFG
            <8     |1234567890ABCDEFG
            >3     |1234567890ABCDEFG
            <<     |1234567890ABCDEFG
            0011000|1234567890ABCDEFG
            <<2    |1234567890ABCDEFG
            >>5    |1234567890ABCDEFG
            0014000|1234567890ABCDEFG
            >>     |1234567890ABCDEFG

        ===> result for not margind file

      <<4   0001000|1234567890ABCDEFG
            0002000*  7890ABCDEFG
      <<4   0003000*4567      DEFG
      >>4   0004000*    1234567890A
            0005000*    12   678
            0006000*      34567890ABC
      >>4   0007000*    1234567890ABCDEFG
      <8    0008000|1234567890ABCDEFG
      >3    0009000*   1234567890ABCDEFG
      <<2   0010000|1234567890ABCDEFG
            0011000|1234567890ABCDEFG
      <<2   0012000|1234567890ABCDEFG
      >>5   0013000*     1234567890ABCDEFG
            0014000*     1234567890ABCDEFG
      >>5   0015000*     1234567890ABCDEFG

        ===> result for margined(m15) file

            0001000|//*CID://+dateR~:#63 option=(m15,p1,tabclear) update#=    2;
      <<4   0002000|1234567890ABCDEFG
            0003000*  7890ABCDE    FG
      <<4   0004000*4567      DE   FG
      >>4   0005000*    1234567890A
            0006000*    12   678
            0007000*    34567890ABC
      >>4   0008000|1234567890ABCDEFG
      <8    0009000|1234567890ABCDEFG
      >3    0010000|1234567890ABCDEFG
      <<2   0011000|1234567890ABCDEFG
            0012000|1234567890ABCDEFG
      <<2   0013000|1234567890ABCDEFG
      >>5   0014000|1234567890ABCDEFG
            0015000|1234567890ABCDEFG
      >>5   0016000|1234567890ABCDEFG
1