Rewrite SQL++ functions.

-Maps SQL function names to internal names.
-Allows SQL++ builtin functions to be case-insensitive.
-Rewrites SQL-92 global aggregates.
-Refactors SQL++ AST visitors.
-Cleans up semantics of COLL_AGG and SQL-92 AGG.

Change-Id: Idb5a7c6780669b27065b0928bec7e4700cfb53a9
Reviewed-on: https://asterix-gerrit.ics.uci.edu/759
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <tillw@apache.org>
diff --git a/asterix-app/src/test/resources/optimizerts/queries_sqlpp/query-issue601.sqlpp b/asterix-app/src/test/resources/optimizerts/queries_sqlpp/query-issue601.sqlpp
index 5f60eb0..1c68428 100644
--- a/asterix-app/src/test/resources/optimizerts/queries_sqlpp/query-issue601.sqlpp
+++ b/asterix-app/src/test/resources/optimizerts/queries_sqlpp/query-issue601.sqlpp
@@ -51,7 +51,7 @@
 
 create  table LineItem(LineItemType) primary key l_orderkey,l_linenumber;
 
-select element {'l_linenumber':l_linenumber,'count_order':tpch.count(l)}
+select element {'l_linenumber':l_linenumber,'count_order':count(l)}
 from  LineItem as l
 group by l.l_linenumber as l_linenumber
 ;