Add handler helpers (#133)

* Add handler helpers

* add necessary docs

ext/handlers/callbackquery.go

@@ -21,6 +21,12 @@ func NewCallback(filter filters.CallbackQuery, r Response) CallbackQuery {
 	}
 }
 
+// SetAllowChannel Enables channel messages for this handler.
+func (cb CallbackQuery) SetAllowChannel(allow bool) CallbackQuery {
+	cb.AllowChannel = allow
+	return cb
+}
+
 func (cb CallbackQuery) HandleUpdate(b *gotgbot.Bot, ctx *ext.Context) error {
 	return cb.Response(b, ctx)
 }

ext/handlers/command.go

@@ -26,6 +26,18 @@ func NewCommand(c string, r Response) Command {
 	}
 }
 
+// SetAllowEdited Enables edited messages for this handler.
+func (c Command) SetAllowEdited(allow bool) Command {
+	c.AllowEdited = allow
+	return c
+}
+
+// SetAllowChannel Enables channel messages for this handler.
+func (c Command) SetAllowChannel(allow bool) Command {
+	c.AllowChannel = allow
+	return c
+}
+
 func (c Command) CheckUpdate(b *gotgbot.Bot, ctx *ext.Context) bool {
 	if ctx.Message != nil {
 		if ctx.Message.Text == "" && ctx.Message.Caption == "" {

ext/handlers/message.go

@@ -24,6 +24,18 @@ func NewMessage(f filters.Message, r Response) Message {
 	}
 }
 
+// SetAllowEdited Enables edited messages for this handler.
+func (m Message) SetAllowEdited(allow bool) Message {
+	m.AllowEdited = allow
+	return m
+}
+
+// SetAllowChannel Enables channel messages for this handler.
+func (m Message) SetAllowChannel(allow bool) Message {
+	m.AllowChannel = allow
+	return m
+}
+
 func (m Message) CheckUpdate(b *gotgbot.Bot, ctx *ext.Context) bool {
 	if ctx.Message != nil {
 		return m.Filter == nil || m.Filter(ctx.Message)