Add libuv license info to LICENSE.txt

Author: brson

LICENSE.txt

@@ -154,6 +154,35 @@ The following third party packages are included:
     SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 
+* The libuv asynchronous I/O library. Code for this package is found
+  in the src/rt/libuv directory, within this distribution. This
+  package is redistributed under the following terms, as noted in its
+  source:
+
+    Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+
+
+* Additional libraries included in libuv carry separate BSD-compatible
+  licenses. See src/rt/libuv/LICENSE for details.
+
+
 The remaining code and documentation in the collective work presented here, as
 well as the collective work itslf, is distributed under the following terms: