code: public AsciiTable setTextAlignment(TextAlignment textAlignment){
  		for(AT_Row row : this.rows){
  			if(row.getType()==TableRowType.CONTENT){
  				row.setTextAlignment(textAlignment);
  			}
  		}
  		return this;
  	}
docs: Sets the text alignment for all cells in the table.
  @param textAlignment new text alignment
  @throws NullPointerException if the argument was null
  @return this to allow chaining
  @throws {@link NullPointerException} if the argument was null