Setting the "help" keyword argument may not fit in one line sometimes. This
patch adds the following convention to calls to add_option() in order to
address that issue in a better way:
1) The "help" keyword must always be the last argument to be passed.
2) If the help string is a literal string or a literal string with some
operation (e.g. "%" operator) and setting the "help" keyword in the code
doesn't fit a line (considering the limit of characters in a line), then
the help string must be a triple-quoted string. That has the advantage of
not having to have several "+" operations for long help strings. In that
case, the help message must start on the next line and the closing
triple-quotes must be on a separate line together with the closing
parenthesis.
The requirement (1) makes it easier to make the style exception in (2)
acceptable.