Use 1.1.0 kotlin

Author: ilya-g

kotlinx-collections-immutable/build.gradle

@@ -1,9 +1,8 @@
 buildscript {
-    ext.kotlin_version = "1.1.0-rc-91"
+    ext.kotlin_version = "1.1.0"
 
     repositories {
         jcenter()
-        maven { url 'http://dl.bintray.com/kotlin/kotlin-eap-1.1' }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"