DEVTOOLS-5507 Include roaring.h as roaring/roaring.h

This is needed to unbundle roaring. Its original cmake build system installs:

     /usr/include/roaring/roaring.h
     /usr/include/roaring/roaring.hh

and declares:

     set_target_properties(roaring::roaring PROPERTIES
       INTERFACE_INCLUDE_DIRECTORIES "/usr/include"
     )

contrib/croaring/CMakeLists.txt

@@ -1,6 +1,6 @@
 add_library(roaring
 	roaring.c
-	roaring.h
-	roaring.hh)
+	roaring/roaring.h
+	roaring/roaring.hh)
 
 target_include_directories (roaring PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})

contrib/croaring/roaring.c

@@ -1,5 +1,5 @@
 /* auto-generated on Tue Dec 18 09:42:59 CST 2018. Do not edit! */
-#include "roaring.h"
+#include "roaring/roaring.h"
 
 /* used for http://dmalloc.com/ Dmalloc - Debug Malloc Library */
 #ifdef DMALLOC

dbms/src/AggregateFunctions/AggregateFunctionGroupBitmapData.h

@@ -1,10 +1,10 @@
 #pragma once
 
-#include <roaring.h>
+#include <roaring/roaring.h>
 #include <IO/ReadHelpers.h>
 #include <IO/WriteHelpers.h>
 #include <boost/noncopyable.hpp>
-#include <roaring.hh>
+#include <roaring/roaring.hh>
 #include <Common/HashTable/SmallTable.h>
 #include <Common/PODArray.h>