Docs: remove site to migrate to iceberg-docs repository

[jackye1995]

This is the first step in Iceberg doc site migration, and the entire site directory is removed. This serves as a lock for us to port all the diff between iceberg and iceberg-docs repo, as all open PRs for doc change will see a merge conflict.

The new website is now deployed using iceberg-docs.

After the port is done, the files in the iceberg-docs repo will be copied back under documentation folder here, completing the migration process.

site will also now be an ignored directory added to .gitignore, the only use of it is to generate javadoc.

[samredai]

Thanks @jackye1995! What is the purpose of the site/docs/javadoc/remove-site directory?

[jackye1995]

oh I think that's due to me running ./gradlew refreshJavadoc on my branch called remove-site. Let me remove that

[rdblue]

Looks good! I merged this.

Just a quick update for anyone that finds this commit, this is part of moving to the new iceberg-docs repo. We plan to follow up with a commit that adds back docs to be updated in master that will be pulled over to the docs repo for every release. So we do still plan to maintain docs that apply to master here, we just want to start with a copy that is in sync with the state of the iceberg-docs markdown.