Support --projects in gerrit_downloader

[iksaif]

I'd like to use gerrit downloader with prefixes. This means using 'projects:prefix' instead of 'project:{^project}`

Here is a quick hack to make it work, but it would be nicer to add a '--projects' option doing that.

$ git diff
diff --git a/GerritDownloader/src/main/java/com/holmsted/gerrit/downloaders/ssh/SshDownloader.java b/GerritDownloader/src/main/java/com/holmsted/gerrit/downloaders/ssh/SshDownloader.java
index 862d437..ce4fd4d 100644
--- a/GerritDownloader/src/main/java/com/holmsted/gerrit/downloaders/ssh/SshDownloader.java
+++ b/GerritDownloader/src/main/java/com/holmsted/gerrit/downloaders/ssh/SshDownloader.java
@@ -255,9 +255,9 @@ public class SshDownloader extends AbstractGerritStatsDownloader {
                 throw new IllegalStateException("No project name defined!");
             }
             if (afterDate != null) {
-                this.gerritQuery = String.format("project:{^%s} after:{%s}", projectNameList, afterDate);
+                this.gerritQuery = String.format("projects:%s after:{%s}", projectNameList, afterDate);
             } else {
-                this.gerritQuery = String.format("project:{^%s}", projectNameList);
+                this.gerritQuery = String.format("projects:%s", projectNameList);
             }
         }