Turn on incremental by default.

Change-Id: I1d3531f37802ab9a7d0251dbfe687a03dce82f92
diff --git a/dev/codeserver/java/com/google/gwt/dev/codeserver/Options.java b/dev/codeserver/java/com/google/gwt/dev/codeserver/Options.java
index 5ab8609..4e4409d 100644
--- a/dev/codeserver/java/com/google/gwt/dev/codeserver/Options.java
+++ b/dev/codeserver/java/com/google/gwt/dev/codeserver/Options.java
@@ -56,7 +56,7 @@
   private ImmutableList<String> args;
   private Set<String> tags = new LinkedHashSet<String>();
 
-  private boolean incremental = false;
+  private boolean incremental = true;
   private boolean noPrecompile = false;
   private boolean isCompileTest = false;
   private File workDir;