Update README/RELEASENOTES from main.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=119211619

README.md

@@ -81,15 +81,3 @@ and copy `library.jar` to the libs folder of your new project.
 
 To develop ExoPlayer using Android Studio, simply open the ExoPlayer project in
 the root directory of the repository.
-
-#### Using Eclipse ####
-
-To develop ExoPlayer using Eclipse:
-
-  1. Install Eclipse and setup the [Android SDK][].
-  1. Open Eclipse and navigate to File->Import->General->Existing Projects into
-     Workspace.
-  1. Select the root directory of the repository.
-  1. Import the projects.
-
-[Android SDK]: http://developer.android.com/sdk/index.html

RELEASENOTES.md

 # Release notes #
 
+### Current dev branch ###
+
+### r1.5.7 ###
+
+* OGG: Support added for OGG.
+* FLAC: Support for FLAC extraction and playback (via an extension).
+* HLS: Multiple audio track support (via Renditions).
+* FMP4: Support multiple tracks in fragmented MP4 (not applicable to
+  DASH/SmoothStreaming).
+* WAV: Support for 16-bit WAV files.
+* MKV: Support non-square pixel formats.
+* Misc bug fixes.
+
 ### r1.5.6 ###
 
-* MP3: Fix mono streams playing at 2x speed on some MediaTek based devices (#801).
+* MP3: Fix mono streams playing at 2x speed on some MediaTek based devices
+  (#801).
 * MP3: Fix playback of some streams when stream length is unknown.
 * ID3: Support multiple frames of the same type in a single tag.
-* EIA608: Correctly handle repeated control characters, fixing an issue in which captions would
-  immediately disappear.
-* AVC3: Fix decoder failures on some MediaTek devices in the case where the first buffer fed to the
-  decoder does not start with SPS/PPS NAL units.
+* EIA608: Correctly handle repeated control characters, fixing an issue in which
+  captions would immediately disappear.
+* AVC3: Fix decoder failures on some MediaTek devices in the case where the
+  first buffer fed to the decoder does not start with SPS/PPS NAL units.
 * Misc bug fixes.
 
 ### r1.5.5 ###
@@ -96,9 +110,10 @@
 
 ### r1.3.2 ###
 
-* DataSource improvements: `DefaultUriDataSource` now handles http://, https://, file://, asset://
-  and content:// URIs automatically. It also handles file:///android_asset/* URIs, and file paths
-  like /path/to/media.mp4 where the scheme is omitted.
+* DataSource improvements: `DefaultUriDataSource` now handles http://, https://,
+  file://, asset:// and content:// URIs automatically. It also handles
+  file:///android_asset/* URIs, and file paths like /path/to/media.mp4 where the
+  scheme is omitted.
 * HLS: Fix for some ID3 events being dropped.
 * HLS: Correctly handle 0x0 and floating point RESOLUTION tags.
 * Mp3Extractor: robustness improvements.