Use RestApiServlet and SSH commands for plugin actions

This change is adding one endpoint with three methods:

* GET /config/server/readonly~readonly
* PUT /config/server/readonly~readonly
* DELETE /config/server/readonly~readonly

and based on this endpoint, three SSH commands:

* ssh host readonly get
* ssh host readonly put
* ssh host readonly delete

Change-Id: I1797906aebb30674c7c37ecfe03a8b944b631299
9 files changed
tree: 3f7407d921a619c940377e9141412387e01f2738
  1. src/
  2. tools/
  3. .gitignore
  4. bazlets.bzl
  5. BUILD
  6. external_plugin_deps.bzl
  7. WORKSPACE