Follow-up to 'Remove standalone build mode'

Add information on how to import 'lfs' plugin to the eclipse
workspace in a way that all JGit dependencies are properly resolved.

Change-Id: I111d2e156fd4b79e1b2d9250a02f43d5c4232491

src/main/resources/Documentation/build.md

diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index 630b0d6..eaa2a5c 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -22,13 +22,26 @@
   bazel test plugins/@PLUGIN@:@PLUGIN@_tests
 ```
 
-This project can be imported into the Eclipse IDE.
-Add the plugin name to the `CUSTOM_PLUGINS` set in
-Gerrit core in `tools/bzl/plugins.bzl`, and execute:
+This project can be imported into the Eclipse IDE in the following steps:
 
-```
-  ./tools/eclipse/project.py
-```
+1. Add the plugin name to the `CUSTOM_PLUGINS` set in Gerrit core in
+`tools/bzl/plugins.bzl`.
+
+1. Add sources for LFS related JGit libraries set in `import_jgit_sources`
+method of Gerrit core `tools/eclipse/project.py`:
+    ```
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.http.apache/src')
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.http.apache/resources')
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.lfs/src')
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.lfs/resources')
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.lfs.server/src')
+    classpathentry('src', 'modules/jgit/org.eclipse.jgit.lfs.server/resources')
+    ```
+
+1. Finally execute:
+    ```
+    ./tools/eclipse/project.py
+    ```
 
 How to build the Gerrit Plugin API is described in the [Gerrit
 documentation](../../../Documentation/dev-bazel.html#_extension_and_plugin_api_jar_files).