Serialization plugin GSK build

Fixed issue when serialDesc property getter was generated, but backing field not.

Respect @Serializable(with=...) on property

Calling 3-arg readElementValue for support of custom contexts

Ability to nest context-based serializer

Migration to 1.2-Beta2

Use polymorphicSerializer prior to default

Don't use polymorphic serializers for all java classes

Docs and maven project update

Remove plugin runtime dependency on stdlib

settings.gradle

@@ -180,7 +180,10 @@ include ":kotlin-build-common",
         ':kotlin-gradle-plugin:plugin-marker',
         ':kotlin-allopen:plugin-marker',
         ':kotlin-noarg:plugin-marker',
-        ":test-instrumenter"
+        ":test-instrumenter",
+
+        ":kotlinx-serialization-compiler-plugin",
+        ":kotlinx-gradle-serialization-plugin"
 
 def isTeamcityBuild = hasProperty("teamcity") || System.getenv("TEAMCITY_VERSION") != null
 def includeUltimate = hasProperty("intellijUltimateEnabled") && intellijUltimateEnabled != 'false'
@@ -294,3 +297,6 @@ project(':libraries:kotlin-prepush-hook').projectDir = "$rootDir/libraries/tools
 project(':kotlin-gradle-plugin:plugin-marker').projectDir = file("$rootDir/libraries/tools/kotlin-gradle-plugin/plugin-marker")
 project(':kotlin-allopen:plugin-marker').projectDir = file("$rootDir/libraries/tools/kotlin-allopen/plugin-marker")
 project(':kotlin-noarg:plugin-marker').projectDir = file("$rootDir/libraries/tools/kotlin-noarg/plugin-marker")
+
+project(':kotlinx-serialization-compiler-plugin').projectDir = file("$rootDir/plugins/kotlin-serialization/kotlin-serialization-compiler")
+project(':kotlinx-gradle-serialization-plugin').projectDir = file("$rootDir/libraries/tools/kotlin-serialization")