KT-3729 Quick documentation support

#KT-3729 Fixed

idea/testData/editor/quickDoc/OnMethodUsage.kt

@@ -0,0 +1,15 @@
+/**
+ Some documentation
+
+ @param a - Some int
+ * @param b: String
+ */
+fun testMethod(a: Int, b: String) {
+
+}
+
+fun test() {
+    <caret>testMethod(1, "value")
+}
+
+// INFO: <b>internal</b> <b>fun</b> testMethod(a: jet.Int, b: jet.String): jet.Unit <i>defined in</i> root package<br/><p>Some documentation<br/><br/><b>@param</b> - <i>a</i> - Some int<br/><b>@param</b> - <i>b</i>: String<br/></p>