std: Update stable since for core::char

Also add `#[doc(hidden)]` to a few internal functions.

Author: alexcrichton

src/libcore/char.rs

@@ -14,7 +14,7 @@
 
 #![allow(non_snake_case)]
 #![doc(primitive = "char")]
-#![stable(feature = "rust1", since = "1.0.0")]
+#![stable(feature = "core_char", since = "1.2.0")]
 
 use iter::Iterator;
 use mem::transmute;
@@ -225,6 +225,7 @@ impl CharExt for char {
 #[inline]
 #[unstable(feature = "char_internals",
            reason = "this function should not be exposed publicly")]
+#[doc(hidden)]
 pub fn encode_utf8_raw(code: u32, dst: &mut [u8]) -> Option<usize> {
     // Marked #[inline] to allow llvm optimizing it away
     if code < MAX_ONE_B && !dst.is_empty() {
@@ -258,6 +259,7 @@ pub fn encode_utf8_raw(code: u32, dst: &mut [u8]) -> Option<usize> {
 #[inline]
 #[unstable(feature = "char_internals",
            reason = "this function should not be exposed publicly")]
+#[doc(hidden)]
 pub fn encode_utf16_raw(mut ch: u32, dst: &mut [u16]) -> Option<usize> {
     // Marked #[inline] to allow llvm optimizing it away
     if (ch & 0xFFFF) == ch && !dst.is_empty() {