Spellcheck: common misspellings in the entire source tree

scripts/http-fileupload-exploiter.nse

@@ -45,7 +45,7 @@ payload in the comment.
 -- 80/tcp open  http    syn-ack
 -- |   Testing page /post.html
 -- |
--- |     Succesfully uploaded and executed payloads:
+-- |     Successfully uploaded and executed payloads:
 -- |      Filename: 1.php, MIME: text/plain
 -- |_     Filename: 1.php3, MIME: text/plain
 ---
@@ -152,7 +152,7 @@ end
 local makeAndCheckRequests = function(uploadspaths)
 
   local exit = 0
-  local output = {"Succesfully uploaded and executed payloads: "}
+  local output = {"Successfully uploaded and executed payloads: "}
 
   for i=1, #listofrequests, 1 do
     listofrequests[i]:make()