Fixing a few errors post testing

collects/web-server/compat/0/servlet/servlet-structs.rkt

@@ -1,5 +1,6 @@
 #lang racket/base
 (require racket/contract
+         web-server/servlet/servlet-structs
          web-server/http)  
 
 (define k-url?

collects/web-server/managers/lru.rkt

@@ -2,6 +2,7 @@
 (require racket/match
          racket/contract)
 (require "manager.rkt"
+         web-server/http
          web-server/servlet/servlet-structs)
 (provide/contract
  [create-LRU-manager 

collects/web-server/managers/none.rkt

@@ -1,7 +1,8 @@
 #lang racket/base
 (require racket/contract)
 (require "manager.rkt")
-(require web-server/servlet/servlet-structs)
+(require web-server/servlet/servlet-structs
+         web-server/http)
 (provide/contract
  [create-none-manager
   (-> 

collects/web-server/managers/timeouts.rkt

@@ -3,6 +3,7 @@
          racket/contract)
 (require "manager.rkt")
 (require web-server/private/timer
+         web-server/http
          web-server/servlet/servlet-structs)
 (provide/contract
  [create-timeout-manager 

collects/web-server/scribblings/contracts.scrbl

@@ -14,7 +14,7 @@ provides an indirection from application-specific response formats and the inter
 HTTP response format, @racket[response].
 
 @deftogether[[
-@defthing[(can-be-response? [x any/c])
+@defproc[(can-be-response? [x any/c])
           boolean?]
 @defproc[(any->response [x any/c])
          (or/c false/c response?)]
@@ -24,6 +24,7 @@ HTTP response format, @racket[response].
 
    @racket[any->response] coerces any value into a response or returns @racket[#f] if coercion is not possible.
    @racket[any->response] guarantees that any @racket[response?] input must always be returned exactly (i.e. @racket[eq?].)
+   The default always returns @racket[#f], signifying that no coercion is possible.
    
    @racket[can-be-response?] returns @racket[#t] if @racket[x] is a response or can be turned into a response by calling
    @racket[any->response].