Merge pull request #479 from vstakhov/master

Add new event type for conflicts.
Add new large contributors the AUTHORS, thank you for your work!
Cosmetic fixes from previous merge
Allow to directly write manifest into a FILE * or a struct sbuf *

Add 2 new functions:
pkg_emit_manifest_sbuf and pkg_emit_manifest_file
move pkg_emit_manifest_file into public API and use it

Now pkg info -R directly output the manifest to stdout