Fix skip help text

[peterfab9845]

The help text didn't match the behavior, so I updated the help text to fit the code. The other way would be easy, but this was even easier. Either way, no missing functionality:

	Type A (current)	Type B
Skip one first	skip [1]	skip [1]
Skip one later	skip <i>	skip <i> <i> (not obvious IMO)
Skip first n	skip 1 <n>	skip <n>
Skip range	skip <a> <b>	skip <a> <b>