Improve code readability

Cleaning up unused imports + changing order of operations on a value that is 0 by default

src/Internal/Tools/Iddict.elm

@@ -43,8 +43,6 @@ do not need to generate identifiers yourself.
 import FastDict as Dict exposing (Dict)
 import Internal.Config.Text as Text
 import Internal.Tools.Json as Json
-import Json.Decode as D
-import Json.Encode as E
 
 
 {-| The Iddict data type.
@@ -66,8 +64,8 @@ coder x =
                     { cursor =
                         Dict.keys d
                             |> List.maximum
-                            |> Maybe.withDefault -1
-                            |> (+) 1
+                            |> Maybe.map ((+) 1)
+                            |> Maybe.withDefault 0
                             |> max (Dict.size d)
                             |> max c
                     , dict = d

src/Internal/Values/Timeline.elm

@@ -72,8 +72,6 @@ import Internal.Tools.Hashdict as Hashdict exposing (Hashdict)
 import Internal.Tools.Iddict as Iddict exposing (Iddict)
 import Internal.Tools.Json as Json
 import Internal.Config.Text as Text
-import Json.Decode as D
-import Json.Encode as E
 import Recursion
 import Recursion.Traverse
 import Set exposing (Set)

tests/Test/Values/Timeline.elm

@@ -5,7 +5,6 @@ import Fuzz exposing (Fuzzer)
 import Internal.Filter.Timeline as Filter exposing (Filter)
 import Internal.Values.Timeline as Timeline exposing (Batch, Timeline)
 import Json.Decode as D
-import Json.Encode as E
 import Test exposing (..)
 import Test.Filter.Timeline as TestFilter
 import Internal.Tools.Json as Json