Handle POST request, and some refactors

src/frank/dsl.cr

@@ -1,3 +1,7 @@
 def get(path, &block : Frank::Request -> String)
-  Frank::Handler::INSTANCE.add_route(path, block)
+  Frank::Handler::INSTANCE.add_route("GET", path, &block)
+end
+
+def post(path, &block : Frank::Request -> String)
+  Frank::Handler::INSTANCE.add_route("POST", path, &block)
 end

src/frank/handler.cr

@@ -19,15 +19,16 @@ class Frank::Handler < HTTP::Handler
     end
   end
 
-  def add_route(path, handler)
-    @routes << Route.new(path, handler)
+  def add_route(method, path, &handler : Frank::Request -> String)
+    @routes << Route.new(method, path, &handler)
   end
 
   def exec_request(request)
     components = request.path.split "/"
     @routes.each do |route|
-      frank_request = route.match(request, components)
-      if frank_request
+      params = route.match(request.method, components)
+      if params
+        frank_request = Request.new(params)
         return route.handler.call(frank_request)
       end
     end

src/frank/route.cr

@@ -1,11 +1,12 @@
 class Frank::Route
   getter handler
 
-  def initialize(path, @handler)
+  def initialize(@method, path, &@handler : Frank::Request -> String)
     @components = path.split "/"
   end
 
-  def match(request, components)
+  def match(method, components)
+    return nil unless method == @method
     return nil unless components.length == @components.length
 
     params = nil
@@ -20,6 +21,6 @@ class Frank::Route
     end
 
     params ||= {} of String => String
-    Request.new(params)
+    params
   end
 end