start fill new docs for logging in bot

docs/tgbotapi/logs.md

@@ -0,0 +1,15 @@
+# Logging
+
+In this library we are using [KSLog](/kslog) for logging of events in telegram bots. There are several ways to set it
+up and configure.
+
+* Globally, you may change [DefaultKTgBotAPIKSLog]() logger __BEFORE__ creating of your bots
+* Granular, you may configure and pass `logger` variable to the `KtorRequestsExecutor`
+
+Besides, you always may pass your logger to the bot via `KtorRequestsExecutorBuilder`:
+
+```kotlin
+val bot = telegramBot(YOUR_TOKEN) {
+    logger = KSLog("SomeLogger")
+}
+```