Add docs

src/kemal/dsl.cr

@@ -1,3 +1,6 @@
+# Kemal DSL is defined here and it's baked into global scope.
+# The DSL currently consists of HTTP verbs(get post put patch delete options),
+# WebSocket(ws) and custom error handler(error).
 HTTP_METHODS = %w(get post put patch delete options)
 
 {% for method in HTTP_METHODS %}

src/kemal/static_file_handler.cr

@@ -1,3 +1,8 @@
+# Kemal::StaticFileHandler is used to serve static files(.js/.css/.png e.g).
+# This handler is on by default and you can disable it like.
+#
+#   serve_static false
+#
 class Kemal::StaticFileHandler < HTTP::StaticFileHandler
   def call(context)
     return call_next(context) if context.request.path.not_nil! == "/"

src/kemal/view.cr

@@ -1,3 +1,6 @@
+# This file contains the built-in view templates that Kemal uses.
+# Currently it contains templates for 404 and 500 error codes.
+
 # Template for 404 Not Found
 def render_404
   template = <<-HTML