Merge pull request #13 from jaredhoberock/master

Eliminate superfluous exclusive_scan declaration in synopsis
Merge pull request #14 from jaredhoberock/master

Add effects clauses for special forms of reduce, exclusive_scan, & inclu...
Merge pull request #15 from jaredhoberock/master

Fix inclusive_scan's general signature & eliminate innermost namespace
Added a sentence that was mistakenly removed. Also fixed name to remove &&
Update a comment explaining why a section was deleted.
Merge branch 'master' of https://github.com/cplusplus/parallelism-ts