Replace the Google-specific 'CL' term with 'change'

Change-Id: Ic97e649916b2316298da64c41ae0ba1eb6738a8f

src/main/java/com/googlesource/gerrit/plugins/download/command/BranchCommand.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/download/command/BranchCommand.java b/src/main/java/com/googlesource/gerrit/plugins/download/command/BranchCommand.java
index e38ccd4..fd36718 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/download/command/BranchCommand.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/download/command/BranchCommand.java
@@ -37,13 +37,18 @@
         + QuoteUtil.quote(url)
         + " "
         + ref
-        + " && git checkout -b CL-"
+        + " && git checkout -b change-"
         + id.replaceAll("/", "-")
         + " FETCH_HEAD";
   }
 
   @Override
   String getRepoCommand(String url, String id) {
-    return "repo download -b CL-" + id.replaceAll("/", "-") + " " + QuoteUtil.quote(url) + " " + id;
+    return "repo download -b change-"
+        + id.replaceAll("/", "-")
+        + " "
+        + QuoteUtil.quote(url)
+        + " "
+        + id;
   }
 }

src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java b/src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java
index f85ffb4..e017bd3 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java
@@ -141,14 +141,14 @@
 
   /**
    * @param url The project URL this change is for.
-   * @param ref Git named ref to this CL/patchset.
-   * @param id The CL/PS numbers.
+   * @param ref Git named ref to this change/patchset.
+   * @param id The change/PS numbers.
    */
   abstract String getCommand(String url, String ref, String id);
 
   /**
    * @param url The project URL this change is for.
-   * @param id The CL/PS numbers.
+   * @param id The change/PS numbers.
    */
   String getRepoCommand(String url, String id) {
     // Most commands don't support this, so default it to nothing.