Merge pull request #640 from ReactiveCocoa/do-and-subscribe

Describe -do… and -subscribe… in Basic Operators document
Merge pull request #635 from ReactiveCocoa/deprecate-sequence-many

Deprecate -sequenceMany:, rename -sequenceNext: to -then:
Remove FRP section entirely, combine it with the intro
Remove unnecessary FRP shoutout
List all the patterns that RAC unifies
More understandable phrasing for how RAC models values
Rephrase the example about setting a textfield to the current time
Combine the two sentences about composing signals
Merge pull request #642 from ReactiveCocoa/newcomers-guide

Newcomers' guide
Merge branch 'master' into 2.0-development
implement -concat as -flatten:1
Merge pull request #648 from ReactiveCocoa/concat-as-flatten

Implement -concat as -flatten:1
Merge branch 'master' into 2.0-development
Add test which reproduces the issue #651
Overwrite super's designated initializer
Merge branch '2.0-development' into racobserve-change-dictionary

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACKVOWrapper.m
	ReactiveCocoaFramework/ReactiveCocoaTests/RACKVOWrapperSpec.m
Renamed RAC specific KVO change dictionary keys.
Clarified docs.
Always include RAC specific KVO change dictionary values.
Remove disposables cleanup.