Move Path extensions to the new package kotlin.io.path

This avoids the conflict with the existing top-level functions in
kotlin.io package.

#KT-19192

libraries/stdlib/jdk7/java9/module-info.java

@@ -3,7 +3,7 @@ module kotlin.stdlib.jdk7 {
     requires transitive kotlin.stdlib;
 
     exports kotlin.jdk7;
-    exports kotlin.io.jdk7;
+    exports kotlin.io.path;
 
     exports kotlin.internal.jdk7 to kotlin.stdlib.jdk8;
     opens kotlin.internal.jdk7 to kotlin.stdlib;

libraries/stdlib/jdk7/src/kotlin/io/path/PathReadWrite.kt

@@ -6,9 +6,8 @@
 @file:Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER", "RedundantVisibilityModifier", "RedundantUnitReturnType", "SameParameterValue")
 @file:JvmMultifileClass
 @file:JvmName("PathsKt")
-@file:kotlin.jvm.JvmPackageName("kotlin.io.jdk7")
 
-package kotlin.io
+package kotlin.io.path
 
 import java.io.*
 import java.nio.charset.Charset

libraries/stdlib/jdk7/src/kotlin/io/path/PathUtils.kt

@@ -6,9 +6,8 @@
 @file:Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER", "RedundantVisibilityModifier")
 @file:JvmMultifileClass
 @file:JvmName("PathsKt")
-@file:kotlin.jvm.JvmPackageName("kotlin.io.jdk7")
 
-package kotlin.io
+package kotlin.io.path
 
 import java.io.IOException
 import java.nio.file.*

libraries/stdlib/jdk7/test/PathExtensionsTest.kt

@@ -7,6 +7,7 @@ package kotlin.jdk7.test
 
 import java.io.IOException
 import java.nio.file.*
+import kotlin.io.path.*
 import kotlin.test.*
 
 class PathExtensionsTest {

libraries/stdlib/jdk7/test/PathReadWriteTest.kt

@@ -7,7 +7,7 @@ package kotlin.jdk7.test
 
 import java.nio.file.Files
 import java.nio.file.StandardOpenOption
-import java.util.*
+import kotlin.io.path.*
 import kotlin.test.*
 
 class PathReadWriteTest {