added a failing test
just use a plain object as the subscription identifier
use NSNumbers as subscriber IDs
Declare -[RACTuple rac_sequence] as a property.
Add -[NSEnumerator rac_sequence].
Fixed some formatting.
use -enumerateObjectsUsingBlock: so it tracks the index for us
Merge pull request #266 from EnthusiasticCode/nsenumerator-sequence

Add -[NSEnumerator rac_sequence].
Make NSEumerator+RACSequenceAdditions.h public for iOS too

CC @Coneko
Merge pull request #259 from github/fix-combine-latest-cycle

Fix +combineLatest: cycle