Add Tab strip to Selection Screen

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*Tabbed block.

selection-screen begin of tabbed block tabb1 for 9 lines.
selection-screen tab (15) text-006 user-command ucomm1
 default screen 101.
selection-screen tab (15) text-007 user-command ucomm2
 default screen 102.
selection-screen tab (17) text-008 user-command ucomm3
 default screen 103.
selection-screen end of block tabb1.

selection-screen begin of screen 101 as subscreen.
parameter: p_field1 type i.
selection-screen end of screen 101.

selection-screen begin of screen 102 as subscreen.
parameter: p_field2 type i.
selection-screen end of screen 102.

selection-screen begin of screen 103 as subscreen.
parameter: p_field3 type i.
selection-screen end of screen 103.