Remove redundant session stuff

spec/config_spec.cr

@@ -23,14 +23,6 @@ describe "Config" do
     config.host_binding.should eq "127.0.0.1"
   end
 
-  it "sets session values" do
-    config = Kemal.config
-    config.session["name"] = "kemal"
-    config.session["expire_time"] = 1.hours
-    config.session["name"].as(String).should eq "kemal"
-    config.session["expire_time"].as(Time::Span).should eq 1.hours
-  end
-
   it "adds a custom handler" do
     config = Kemal.config
     config.add_handler CustomTestHandler.new

src/kemal.cr

@@ -18,8 +18,6 @@ module Kemal
     config.server.tls = config.ssl
     {% end %}
 
-    Kemal::Sessions.run_reaper!
-
     unless Kemal.config.error_handlers.has_key?(404)
       error 404 do |env|
         render_404

src/kemal/config.cr

@@ -15,14 +15,13 @@ module Kemal
     {% end %}
 
     property host_binding, ssl, port, env, public_folder, logging, running,
-      always_rescue, serve_static : (Bool | Hash(String, Bool)), server, session : Hash(String, Time::Span | String), extra_options
+      always_rescue, serve_static : (Bool | Hash(String, Bool)), server, extra_options
 
     def initialize
       @host_binding = "0.0.0.0"
       @port = 3000
       @env = "development"
       @serve_static = {"dir_listing" => false, "gzip" => true}
-      @session = {"name" => "kemal_session", "expire_time" => 48.hours}
       @public_folder = "./public"
       @logging = true
       @logger = nil