updating changelogs and version to 1.8.0-0.27b0 (open-telemetry#2338)

updating changelogs and version to 1.8.0-0.27b0 (open-telemetry#2338)

updating changelogs and version to 1.7.1-0.26b1 (open-telemetry#2274)

updating changelogs and version to 1.7.0-0.26b0 (open-telemetry#2272)

Prepare release v1.6.2 and 0.25b2 (open-telemetry#2230)

updating changelogs and version to 1.6.1-0.25b1 (open-telemetry#2223)

updating changelogs and version to 1.6.0-0.25b0 (open-telemetry#2193)

updating changelogs and version to 1.5.0-0.24b0 (open-telemetry#2069)

hotfix: 1.4.1 0.23b2 (open-telemetry#1999)

updating changelogs and version to 1.4.0-0.23b0 (open-telemetry#1965)