docs(changelog): tweak changelog

docs(CHANGELOG): add changelog for 2.0.2

chore(release): v2.1.0-beta.0

chore(release): v2.0.1

chore(release): v2.0.0 proprioception-reinforcement

chore(release): v2.0.0-rc.7

chore(release): bump Angular version to 2.0.0-rc.6 in package.json

docs(changelog): update change log to rc.5

Closes angular#10599

build: fix and document the symlinks scripts for Windows

Closes angular#10213

docs(changelog): change log and package.json to rc4

Closes angular#9727