Adds finite (counted) traversals.
Removes the typedef for linear searches.
Generators are traversals.
RXTraversalArray is actually over traversals.
Array construction is over traversals.
Adds half-implemented convolution.
Adds a convenient typedef for temporary traversal elements.
Moves the unknown traversal count constant into RXTraversal.{h,m}.
Interval traversals use RXTraversalElement.
NSEnumerator is a traversal.
Corrects a test of RXTraversalArray.
Updates the readme sample to import the correct header.
Half-formed attempt at copying enumerated objects into a buffer, commented out.
Half-finished attempt at convolution.
Merge branch 'develop' into feature/convolution

Conflicts:
	RXCollections.xcodeproj/project.pbxproj
	RXCollections/RXFold.m
	RXCollections/RXIntervalTraversal.m
	RXCollections/RXTraversalArray.m
Adds an RXMin function.
RXTuple describes null elements as (null).
Exposes RXHeapFastEnumerationState for e.g. subclassing.
Corrects enumeration traversals’ use of internal state.
Implements convolution.

There are two interfaces to convolution, one producing tuples, and the other producing values provided by a block to which it passes the count and a buffer containing the corresponding elements of each sequence.