Add vk bridge (#1372)

* Add vk bridge

* Vk bridge attachments

* Vk bridge forwarded messages

* Vk bridge sample config and code cleanup

* Vk bridge add vendor

* Vk bridge message edit

* Vk bridge: fix fetching names of other bots

* Vk bridge: code cleanup

* Vk bridge: fix shadows declaration

* Vk bridge: remove UseFileURL

vendor/github.com/SevereCloud/vksdk/v2/api/captcha.go

@@ -0,0 +1,7 @@
+package api
+
+// CaptchaForce api method.
+func (vk *VK) CaptchaForce(params Params) (response int, err error) {
+	err = vk.RequestUnmarshal("captcha.force", &response, params)
+	return
+}