Add initial overview and configuration docs

Introduce the overview of what the plugin does
and describe the configuration parameters required.

Change-Id: Id21973ae92984dfb2f8a65a961710485f19990b8

README.md

diff --git a/README.md b/README.md
index 9c7e361..4bbd207 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,4 @@
 # plugin-manager
-Gerrit web-based plugin manager
+Gerrit web-based plugin manager.
 
-To enable this plugin, `plugins.allowRemoteAdmin = true` is required in
-gerrit.config.
-
-Also note that the use of this plugin is restricted to Gerrit administrators.
+To enable this plugin, please look at the [configuration guide](src/main/resources/Documentation/config.md)
\ No newline at end of file

src/main/resources/Documentation/about.md

diff --git a/src/main/resources/Documentation/about.md b/src/main/resources/Documentation/about.md
new file mode 100644
index 0000000..bab92d3
--- /dev/null
+++ b/src/main/resources/Documentation/about.md
@@ -0,0 +1,12 @@
+This plugin adds support for discovering and installing other plugins
+to Gerrit.
+
+The list of plugins are taken from the following sources:
+
+- Internal core plugins contained in the gerrit.war
+- Plugins built on the [Gerrit CI][1] or another configurable location
+  for the stable branch that Gerrit is built
+
+**NOTE**: Management of plugins is restricted to Gerrit Administrators.
+
+[1]: https://gerrit-ci.gerritforge.com
\ No newline at end of file

src/main/resources/Documentation/config.md

diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
new file mode 100644
index 0000000..ed9f9f0
--- /dev/null
+++ b/src/main/resources/Documentation/config.md
@@ -0,0 +1,40 @@
+How to enable
+-------------
+
+The plugin-manager requires the ability to administer the plugins in Gerrit,
+using the [Gerrit's `plugins.allowRemoteAdmin = true`][1] setting.
+
+Configuration
+-------------
+
+The other plugin-specific settings are defined in the `[plugin-manager]` section
+in the gerrit.config.
+
+jenkinsUrl
+:   URL of the Jenkins CI responsible for building and validating the plugins for
+    the current stable branch of Gerrit.
+    Default value: https://gerrit-ci.gerritforge.com
+
+
+Plugin discovery
+----------------
+
+The compatible plugins are retrieved from a site of build artifacts that are
+following the view setup of the gerrit-ci-scripts project. There is one view
+per Gerrit stable branch (e.g. `Plugins-stable-3.0` contains all the artifacts
+of the plugins built against the Gerrit stable-3.0 branch).
+
+Only the plugins with a job in the corresponding view and having at least one
+successful build will be shown in the list and be discoverable.
+
+It is possible to control the list of plugins discoverable by editing the
+corresponding view.
+
+*DISCLAIMER*: The plugin-manager aims at allowing the discovery and easy
+download and setup of plugins into Gerrit. It is the plugin's maintainer
+responsibility to maintain the build an end-to-end test of the plugin itself.
+One plugin that is building and passes the tests on the CI may well not work
+on Gerrit: testing and validation are always recommended.
+
+[1]: https://gerrit-review.googlesource.com/Documentation/config-gerrit.html#plugins.allowRemoteAdmin
+[2]: https://gerrit.googlesource.com/gerrit-ci-scripts
\ No newline at end of file