Introduced -target and -list_targets flags.

Use it like

    $ konanc hello.kt -target iphone

common/build.gradle

@@ -1,10 +1,11 @@
-import org.jetbrains.kotlin.CompileCppToBitcode
+import org.jetbrains.kotlin.CompilePerTarget
 
 // TODO: consider using some Gradle plugins to build and test
 
-
-task compileHash(type: CompileCppToBitcode) {
+task compileHash(type: CompilePerTarget) {
     name 'hash'
+    targetList targetList
+    targetArgs targetArgs
 }
 
 task build {