Support interop modularity

* Add list of included headers into the manifest
* Implement importing "foreign" type declarations
* Implement forward declarations more natively in the compiler
* Represent Objective-C categories as Kotlin extension methods and
  properties

Also:
* Do some refactoring in stub generation
* Call bridges directly in stubs for Objective-C properties

utilities/src/main/kotlin/org/jetbrains/kotlin/cli/utilities/main.kt

@@ -1,6 +1,9 @@
 package org.jetbrains.kotlin.cli.utilities
 
+import org.jetbrains.kotlin.backend.konan.library.impl.KonanLibrary
 import org.jetbrains.kotlin.konan.file.File
+import org.jetbrains.kotlin.konan.properties.loadProperties
+import org.jetbrains.kotlin.utils.addIfNotNull
 import org.jetbrains.kotlin.cli.bc.main as konancMain
 import org.jetbrains.kotlin.native.interop.gen.jvm.interop 
 import org.jetbrains.kotlin.cli.klib.main as klibMain
@@ -8,11 +11,16 @@ import org.jetbrains.kotlin.cli.klib.main as klibMain
 fun invokeCinterop(args: Array<String>) {
     var outputFileName = "nativelib"
     var target = "host"
+    val libraries = mutableListOf<String>()
     for (i in args.indices) {
-        if (args[i].startsWith("-o")) 
-            outputFileName = args.getOrElse(i+1){outputFileName}
-        if (args[i] == "-target") 
-            target = args.getOrElse(i+1){target}
+        val arg = args[i]
+        val nextArg = args.getOrNull(i + 1)
+        if (arg.startsWith("-o"))
+            outputFileName = nextArg ?: outputFileName
+        if (arg == "-target")
+            target = nextArg ?: target
+        if (arg == "-library")
+            libraries.addIfNotNull(nextArg)
     }
 
     val buildDir = File("$outputFileName-build")
@@ -21,12 +29,23 @@ fun invokeCinterop(args: Array<String>) {
     val cstubsName ="cstubs"
     val manifest = File(buildDir, "manifest.properties")
 
+    val importArgs = libraries.flatMap {
+        val library = KonanLibrary(File(it))
+        val manifestProperties = library.manifestFile.loadProperties()
+        // TODO: handle missing properties?
+        val pkg = manifestProperties["pkg"] as String
+        val headerIds = (manifestProperties["includedHeaders"] as String).split(' ')
+        val arg = "$pkg:${headerIds.joinToString(",")}"
+        listOf("-import", arg)
+    }
+
     val additionalArgs = listOf<String>(
         "-generated", generatedDir.path, 
         "-natives", nativesDir.path, 
         "-cstubsname", cstubsName,
         "-manifest", manifest.path,
-        "-flavor", "native")
+        "-flavor", "native"
+    ) + importArgs
 
     val cinteropArgs = (additionalArgs + args.toList()).toTypedArray()
     val cinteropArgsToCompiler = mutableListOf<String>()
@@ -39,7 +58,7 @@ fun invokeCinterop(args: Array<String>) {
         "-o", outputFileName,
         "-target", target,
         "-manifest", manifest.path
-     ) + cinteropArgsToCompiler
+    ) + cinteropArgsToCompiler + libraries.flatMap { listOf("-library", it) }
     konancMain(konancArgs)
 }