Fix all of our pom.xml versions to be 2.1-SNAPSHOT

I meant to keep reusing the 2.1 version number for the entire
2.1 series during development, but botched it during the 2.1.4
development cycle and set it to 2.1.4-SNAPSHOT by mistake.  Put
it back to 2.1-SNAPSHOT since 2.1.4 is released.

Change-Id: I37e206c0609bf3fd94a5aab8ea301c98b7fb013e
Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/pom.xml b/pom.xml
index 13ffb8b..26a065a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -22,7 +22,7 @@
   <groupId>com.google.gerrit</groupId>
   <artifactId>gerrit-parent</artifactId>
   <packaging>pom</packaging>
-  <version>2.1.4-SNAPSHOT</version>
+  <version>2.1-SNAPSHOT</version>
 
   <name>Gerrit Code Review - Parent</name>
   <url>http://code.google.com/p/gerrit/</url>