better docs for the output

[Oleg Sofrygin]

• Describe the output results table(s) for each function
• Define each column and describe what it contains)

For example:

     est_name time   sum_Y_IPW    sum_IPW St.directIPW rule.name
 1: directIPW    0    9.828827   225.6710    0.9564462   TI.set1
 2: directIPW    1   14.841714   308.6067    0.9519073   TI.set1
 3: directIPW    2   21.627479   430.0012    0.9497037   TI.set1
 4: directIPW    3   21.627479   606.0012    0.9643112   TI.set1
 5: directIPW    4   43.571094   868.0025    0.9498030   TI.set1
 6: directIPW    5   61.760385  1241.4314    0.9502507   TI.set1
 7: directIPW    6   66.382274  1802.6454    0.9631751   TI.set1
 8: directIPW    7  116.322109  2638.1985    0.9559085   TI.set1
 9: directIPW    8  198.486284  3871.7562    0.9487348   TI.set1
10: directIPW    9  254.941362  5714.0214    0.9553832   TI.set1
11: directIPW   10  254.941362  8456.0006    0.9698508   TI.set1
12: directIPW   11  397.563386 12563.9928    0.9683569   TI.set1
13: directIPW   12 1225.200094 18784.3937    0.9347756   TI.set1
14: directIPW   13 1816.300699 27581.8941    0.9341488   TI.set1
15: directIPW   14 1816.300699 40628.9102    0.9552954   TI.set1
16: directIPW   15 4927.103677 60323.6409    0.9183222   TI.set1
17: directIPW   16 4927.103677 88105.7038    0.9440774   TI.set1