test(HydraScript): compound assignment

Closes #233

Author: Минин Степан Александрович

tests/HydraScript.IntegrationTests/Samples/compound_assign.js

@@ -0,0 +1,19 @@
+let x = {
+    prop: 2;
+}
+x.prop += 4 + 5 * 3
+x.prop *= 7
+>>> x
+
+let y = 1
+y -= (y + 2) * (3 + 4)
+y /= 5
+>>> y
+
+let arr: number[] = []
+let i = 0
+while (i < 5) {
+    arr ++= [i]
+    i += 1
+}
+>>> arr