Bump all version numbers up to 0.2.21 to be in sync with VS Code plugin

Author: JakeBecker

apps/debugger/mix.exs

@@ -4,7 +4,7 @@ defmodule ElixirLS.Debugger.Mixfile do
   def project do
     [
       app: :debugger,
-      version: "0.2.19",
+      version: "0.2.21",
       build_path: "../../_build",
       config_path: "config/config.exs",
       deps_path: "../../deps",

apps/elixir_ls_utils/mix.exs

@@ -4,7 +4,7 @@ defmodule ElixirLS.Utils.Mixfile do
   def project do
     [
       app: :elixir_ls_utils,
-      version: "0.2.19",
+      version: "0.2.21",
       build_path: "../../_build",
       config_path: "../../config/config.exs",
       deps_path: "../../deps",

apps/language_server/mix.exs

@@ -4,7 +4,7 @@ defmodule ElixirLS.LanguageServer.Mixfile do
   def project do
     [
       app: :language_server,
-      version: "0.2.19",
+      version: "0.2.21",
       elixir: ">= 1.6.5",
       build_path: "../../_build",
       config_path: "config/config.exs",