Spell Apple rdar:// links correctly.
Merge pull request #8 from berkus/patch-1

Spell Apple rdar:// links correctly.
corrected rdar urls
Removed impossible group, for now
added simple future
updated readme with future
map + flatMap for future
map / flatMap added to README
Added arrayexts, disabled
removed maybe
removed optional test
"added" optional flatMap
concurrent chan added
Added chan example
Added maybe cata for Optional

Same linking problem as flatMap