Allow for multi-line abstract.

A fix for https://github.com/rjbs/Dist-Zilla/issues/205
Added support for multi-line abstracts in PodVersion
add a recommended module to recommendations
document that develop requires prereqs are added
clarify that prefix indicates the destination, not the source, of the gathered files
only prompt with the second half of the string

This should look identical, but plugins that feed into the prompt mechanism
will now only see the second part - the part that actually asks the question.