Bump rubygem version up to 0.2.0, now that we're released and all.

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@896711 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/rb/Rakefile b/lib/rb/Rakefile
index cdff774..6263fc6 100644
--- a/lib/rb/Rakefile
+++ b/lib/rb/Rakefile
@@ -82,7 +82,7 @@
     p.summary = "Ruby libraries for Thrift (a language-agnostic RPC system)"
     p.url = "http://incubator.apache.org/thrift/"
     p.include_rakefile = true
-    p.version = "0.1.0"
+    p.version = "0.2.0"
     p.rubygems_version = ">= 1.2.0"
   end