Move from gitbook to docusaurus, build docs in Travis CI (#10970)

* fix: ignore unknown fields in more RPC responses

* Remove mdbook infrastructure

* Delete gitattributes and other theme related items

Move all docs to /docs folder to support Docusaurus

* all docs need to be moved to /docs

* can be changed in the future

Add Docusaurus infrastructure

* initialize docusaurus repo

Remove trailing whitespace, add support for eslint

Change Docusaurus configuration to support `src`

* No need to rename the folder! Change a setting and we're all good to
go.

* Fixing rebase items

* Remove unneccessary markdown file, fix type

* Some fonts are hard to read. Others, not so much. Rubik, you've been
sidelined. Roboto, into the limelight!

* As much as we all love tutorials, I think we all can navigate around a
markdown file. Say goodbye, `mdx.md`.

* Setup deployment infrastructure

* Move docs job from buildkite to travic

* Fix travis config

* Add vercel token to travis config

* Only deploy docs after merge

* Docker rust env

* Revert "Docker rust env"

This reverts commit f84bc208e807aab1c0d97c7588bbfada1fedfa7c.

* Build CLI usage from docker

* Pacify shellcheck

* Run job on PR and new commits for publication

* Update README

* Fix svg image building

* shellcheck

Co-authored-by: Michael Vines <mvines@gmail.com>
Co-authored-by: Ryan Shea <rmshea@users.noreply.github.com>
Co-authored-by: publish-docs.sh <maintainers@solana.com>

docs/set-vercel-project-name.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# Replaces the PROJECT_NAME value in vercel.json commit based on channel or tag
+# so we push the updated docs to the right domain
+
+set -e
+
+if [[ -n $CI_TAG ]]; then
+  NAME=docs-solana-com
+else
+  eval "$(../ci/channel-info.sh)"
+  case $CHANNEL in
+  edge)
+    NAME=edge-docs-solana-com
+    ;;
+  beta)
+    NAME=beta-docs-solana-com
+    ;;
+  *)
+    NAME=docs
+    ;;
+  esac
+fi
+
+sed -i s/PROJECT_NAME/$NAME/g vercel.json