SQL++ parser:
1. refactored asterix-aql to become asterix-lang-common and asterix-lang-aql, where the former is the common part for different languages;
2. added asterix-lang-sqlpp on top of asterix-lang-common;
3. ported parser tests, optimizer tests and runtime tests in asterix-app to their sql++ version, and added parser tests for all the queries.

Change-Id: Ie5af4e3b692ca017ec047a1ba3b404a51beb3a2e
Reviewed-on: https://asterix-gerrit.ics.uci.edu/466
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <tillw@apache.org>
diff --git a/asterix-doc/src/site/site.xml b/asterix-doc/src/site/site.xml
index 6c1e0cb..8fb18ef 100644
--- a/asterix-doc/src/site/site.xml
+++ b/asterix-doc/src/site/site.xml
@@ -90,7 +90,12 @@
       <item name="Filter-Based LSM Index Acceleration" href="aql/filters.html"/>
       <item name="HTTP API to AsterixDB" href="api.html"/>
     </menu>
-
+    
+    <menu name="SQL++">
+      <item name="SQL++ integration into AsterixDB" href="sqlpp/sqlpp-internals.html"/>
+      <item name="The SQL++ query language in AsterixDB" href="sqlpp/sqlpp-in-asterixdb.html"/>
+    </menu>
+    
     <menu ref="reports"/>
 
     <footer>