Add prerequisites

Change-Id: I22e4ce33d842063811ecceee61c744cf724f9bea
diff --git a/bin/git_gerrit_pull b/bin/git_gerrit_pull
index 8a6e47f..96029f7 100755
--- a/bin/git_gerrit_pull
+++ b/bin/git_gerrit_pull
@@ -26,7 +26,7 @@
 };
 
 unless ($url) {
-  print 'git-gerrit-pull https://github.com/KorAP/.../pull/..' . "\n";
+  print 'git_gerrit_pull https://github.com/KorAP/.../pull/..' . "\n";
   exit;
 };
 
@@ -137,3 +137,8 @@
 This script is an alternative to C<import_github_pull_requests>
 that ignores CI results on github and just requires the
 URL of a specific GH pull request to send it through Gerrit.
+
+Prerequisites:
+Remote repository "github"
+For Kustvakt and Koral Java 11 at /usr/lib/jvm/java-1.11.0-openjdk-amd6
+For KorapSRU and KalamarExport-Plugin Java 8 at /usr/lib/jvm/java-1.8.0-openjdk-amd6