Add changelog for 1.2.2

generated with github_changelog_generator

author=false
compare-link=false
issues=false
future-release=v1.2.2

Add changelog for 1.2.1

generated with github_changelog_generator

author=false
compare-link=false
issues=false
future-release=v1.2.1

Add changelog for 1.2.0

generated with github_changelog_generator

author=false
compare-link=false
issues=false
exclude-tags=v1.2.0.rc1
future-release=v1.2.0

Various updates, corrected include path to README.md

Merge pull request grpc-ecosystem#191 from tmc/tmc.better_eof_handling

return err early if EOF to prevent logging in normal conditions

Merge pull request grpc-ecosystem#184 from gengo/feature/browser-example

Add browser examples