Post-release cleanup and fixes (specific to recent repository restructure) (#3290)
Post-release cleanup and fixes (specific to recent repository restructure) (#3290)

1) Fix poms deployment config.
2) Fix documentaiton links in readmes.
3) Update main README (remove `goolge-cloud` metapackage reference).
4) Update `RELEASING.md` to reflect changes. The instructions try to avoid having mysterious scripts running in the release process and also ensures that all disruptive operations (actual release/push) are done explicitly and not somewhere in the middle of a mysterious script.
5) Remove `deploy.sh` and `finalize_release.sh` scripts.
6) Fix few previously broken links (bigquerydatatransfer and compute apidocs links)

googleapis/java-language,googleapis/java-language,googleapis/java-language