Use a separate Knit tool (#1486)

* Use a separate Knit tool version 0.1.2
* Hierarchical knit.properties files are introduced which are
  gathered while walking up the directory tree with the properties
  in knit resources being top-level ones.
* Freemarker templates for "knit.include" (top-level of example files)
  and "test.template" (test template) are introduced with locations that
  are resolved from properties.
* KNIT and TEST_OUT directives are not supported anymore.
 - Knitting is controlled by "knit.dir" and "knit.pattern" props.
 - "test.name" prop or TEST_NAME directive drives test gen.
* All markdown files are now clean of top-level knit-related boilerplate
  (only TEST_NAME directive is remaining in some)
* All example files are renumbered. It affects example-basic-xx,
  which had the legacy numbering with later insertions.
* All auto-generated files now have the correct source-file name
  specified at their beginning, due to consistent use of template
  substitution.
* No need to customize knit.pattern anymore (works out-of-the box)
* "knit.name" is automatically generated based on example's file name
  "example-basic-01" -> "exampleBasic01"
* Not match-pattern-group woodoo anymore, "knit.pattern" cannot have any
  user-defined match groups.
* No need to look for "package xxx" in knitted sources, as the
  example's package is always ${knit.package}.${knit.name}
* Simpler test names:
  testKotlinxCoroutinesGuideBasic01 -> testExampleBasic01
* Replaced END_TOC with END directive
* Build-scripts are improved:
  - Consistent code to use mavenLocal when snapshots versions are used.
  - Proper substitution logic to use Android AAR files so that Dokka has correct links to Google APIs.
  - Google repository is added to all projects.
diff --git a/docs/select-expression.md b/docs/select-expression.md
index f36fa09..5809e7b 100644
--- a/docs/select-expression.md
+++ b/docs/select-expression.md
@@ -1,21 +1,4 @@
-<!--- INCLUDE .*/example-([a-z]+)-([0-9a-z]+)\.kt 
-/*
- * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
- */
-
-// This file was automatically generated from coroutines-guide.md by Knit tool. Do not edit.
-package kotlinx.coroutines.guide.$$1$$2
--->
-<!--- KNIT     ../kotlinx-coroutines-core/jvm/test/guide/.*\.kt -->
-<!--- TEST_OUT ../kotlinx-coroutines-core/jvm/test/guide/test/SelectGuideTest.kt
-// This file was automatically generated from coroutines-guide.md by Knit tool. Do not edit.
-package kotlinx.coroutines.guide.test
-
-import org.junit.Test
-
-class SelectGuideTest {
---> 
-
+<!--- TEST_NAME SelectGuideTest --> 
 
 **Table of contents**
 
@@ -28,9 +11,7 @@
   * [Selecting deferred values](#selecting-deferred-values)
   * [Switch over a channel of deferred values](#switch-over-a-channel-of-deferred-values)
 
-<!--- END_TOC -->
-
-
+<!--- END -->
 
 ## Select Expression (experimental)