Add upperCaseUsername option

With that option the username is converted to uppercase when replacing
the ${user} placeholder in the avatar url.

Change-Id: If3d6d28dd7ec827b7d11393255b8774270bc205c
diff --git a/src/main/java/com/googlesource/gerrit/plugins/avatars/external/ExternalUrlAvatarProvider.java b/src/main/java/com/googlesource/gerrit/plugins/avatars/external/ExternalUrlAvatarProvider.java
index dc38718..b2da42b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/avatars/external/ExternalUrlAvatarProvider.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/avatars/external/ExternalUrlAvatarProvider.java
@@ -38,6 +38,7 @@
   private String avatarChangeUrl;
   private String sizeParameter;
   private boolean lowerCase;
+  private boolean upperCaseUsername;
 
   @Inject
   ExternalUrlAvatarProvider(
@@ -50,6 +51,7 @@
     avatarChangeUrl = cfg.getString("changeUrl");
     sizeParameter = cfg.getString("sizeParameter");
     lowerCase = cfg.getBoolean("lowerCase", false);
+    upperCaseUsername = cfg.getBoolean("upperCaseUsername", false);
     ssl = canonicalUrl != null && canonicalUrl.startsWith("https://");
   }
 
@@ -113,7 +115,9 @@
     if (url == null || replacement == null || !url.contains(placeholder)) {
       return url;
     }
-    if (lowerCase) {
+    if ("${user}".equals(replacement) && upperCaseUsername) {
+      replacement = replacement.toUpperCase();
+    } else if (lowerCase) {
       replacement = replacement.toLowerCase();
     }
 
diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index 0a61965..861a9ab 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -34,5 +34,9 @@
 `plugin.@PLUGIN@.lowerCase`
 :	Convert the username and email to lower case. Default value = false. Optional.
 
+<a id="upperCaseUsername">
+`plugin.@PLUGIN@.upperCaseUsername`
+:	Convert the username upper case. Default value = false. Optional.
+
 Please note that `http://` URLs will be automatically rewritten to
 `https://`, if `gerrit.canonicalWebUrl` uses HTTPS.