Rename KClass.properties and extensionProperties: prepend 'member'

To better emphasize the fact that all returned properties require an instance
of the class they are declared in. Another issue was that
'Some::class.extensionProperties' was sometimes incorrectly perceived as
"get all extension properties available on the class Some"

compiler/testData/codegen/boxWithStdlib/reflection/properties/fakeOverridesInSubclass.kt

@@ -7,10 +7,10 @@ open class Super(val r: String)
 class Sub(r: String) : Super(r)
 
 fun box(): String {
-    val props = javaClass<Sub>().kotlin.declaredProperties
+    val props = javaClass<Sub>().kotlin.declaredMemberProperties
     if (!props.isEmpty()) return "Fail $props"
 
-    val allProps = javaClass<Sub>().kotlin.properties
+    val allProps = javaClass<Sub>().kotlin.memberProperties
     assertEquals(listOf("r"), allProps.map { it.name })
     return allProps.single().get(Sub("OK")) as String
 }