[Feature] Multimap: support adding map values as extra options

src/plugins/lua/multimap.lua

               symbol, rule.symbol, rule.symbol)
           symbol = rule.symbol
         end
+      elseif rule.disable_multisymbol then
+        symbol = rule.symbol
+        if type(opt) == 'table' then
+          table.insert(opt, result)
+        elseif type(opt) ~= nil then
+          opt = {opt,result}
+        else
+          opt = {result}
+        end
       else
         forced = true
       end

test/functional/cases/102_multimap.robot

   Scan File  ${FREEMAIL_CC}
   Expect Symbol With Score And Exact Options  FREEMAIL_CC  19.00  test.com  test1.com  test2.com  test3.com  test4.com  test5.com  test6.com  test7.com  test8.com  test9.com  test10.com  test11.com  test12.com  test13.com  test14.com
 
+MAP - MULTISYMBOL DISABLED
+  Scan File  ${MESSAGE}  Rcpt=user3@example.com
+  Expect Symbol With Exact Options  RCPT_MAP_NOMULTISYM  user3@example.com  SYM1
+
 *** Keywords ***
 Multimap Setup
   ${PLUGIN_CONFIG} =  Get File  ${TESTDIR}/configs/multimap.conf

test/functional/configs/multimap.conf

     map = "${TESTDIR}/configs/maps/multiple.list";
     score = 1.0;
   }
+  RCPT_MAP_NOMULTISYM {
+    type = "rcpt";
+    filter = "email:addr";
+    disable_multisymbol = true;
+    map = "${TESTDIR}/configs/maps/multiple.list";
+    score = 1.0;
+  }
   HEADER_MAP {
     type = "header";
     header = "To";