Introduced support for javascript Math and Kotlin Double to WASM32.

Implemented jsinterop tool for interaction with js math.

backend.native/tests/jsinterop/math.kt

@@ -0,0 +1,16 @@
+import kotlinx.interop.wasm.math.*
+import kotlinx.wasm.jsinterop.*
+
+fun main(args: Array<String>) {
+
+    val e = Math.E
+    val pi = Math.PI
+
+    val sin_pi = Math.sin(pi)
+    val sin_pi_2 = Math.sin(pi/2)
+    val ln_1 = Math.log(1.0)
+    val ln_e = Math.log(e)
+
+    println("e = $e, pi = $pi, sin(pi) = $sin_pi, sin(pi/2) = $sin_pi_2, ln(1) = $ln_1, ln(e) = $ln_e")
+}
+