chore(release): cut the 2.3.0-beta.0 realse and add change log

chore(release): cut angular 2.2.1

chore(release): cut the 2.2.0 upgrade-firebooster release

chore(release): cut v2.2.0-rc.0

chore(release): cut the 2.2.0-beta.0 release

chore(release): cut the 2.1.2 release

chore(release): cut the 2.2.0-beta.0 release and add changelog

chore(release): cut the 2.1.1 release

chore: bump version number and generate CHANGELOG (angular#12247)

docs(changelog): tweak changelog