Update version to 0.4

Optimize references in generated code. Also fixes Kotlin/kotlinx.serialization/issues/65

Fix (again) broken char boxing

Rebased on 1.2.40 and fixed broken compatibility

Fix https://github.com/Kotlin/kotlinx.serialization/issues/107 and code reformatting

(cherry picked from commit d4c307d)

Add correct type parameter information to synthetic declarations

Needed by kapt due to https://github.com/Kotlin/kotlinx.serialization/issues/76

Make correct call to sealed class constructor

Fixes https://github.com/Kotlin/kotlinx.serialization/issues/112

Bump version

1.2.50-eap-1 compatible

idea-runner/build.gradle.kts

@@ -17,8 +17,9 @@ dependencies {
 
 val ideaPluginDir: File by rootProject.extra
 val ideaSandboxDir: File by rootProject.extra
+val serialPluginDir: File by rootProject.extra
 
-runIdeTask("runIde", ideaPluginDir, ideaSandboxDir) {
+runIdeTask("runIde", ideaPluginDir, ideaSandboxDir, serialPluginDir) {
     // TODO: add serialization plugin to pluginDir
     dependsOn(":dist", ":ideaPlugin", ":kotlinx-serialization-compiler-plugin:dist")
 }