Update STB version.

Docs/Urho3D.dox

@@ -178,9 +178,10 @@ Urho3D uses the following third-party libraries:
 - Recast/Detour (http://code.google.com/p/recastnavigation/)
 - SDL 2.0.4 (http://www.libsdl.org/)
 - StanHull (http://codesuppository.blogspot.com/2006/03/john-ratcliffs-code-suppository-blog.html)
-- stb_image 2.10 (http://nothings.org/)
-- stb_image_write 1.01 (http://nothings.org/)
-- stb_vorbis 1.07 (http://nothings.org/)
+- stb_image 2.12 (http://nothings.org/)
+- stb_image_write 1.02 (http://nothings.org/)
+- stb_rect_pack 0.08 (http://nothings.org/)
+- stb_vorbis 1.09 (http://nothings.org/)
 - SQLite 3.8.10.2 (https://www.sqlite.org/)
 - tolua++ 1.0.93 (http://www.codenix.com/~tolua)
 

README.md

@@ -1,8 +1,8 @@
 ![Urho3D logo](https://raw.githubusercontent.com/urho3d/Urho3D/master/bin/Data/Textures/LogoLarge.png)
 
 #Urho3D
-
-[![Join the chat at https://gitter.im/urho3d/Urho3D](https://badges.gitter.im/urho3d/Urho3D.svg)](https://gitter.im/urho3d/Urho3D?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+
+[![Join the chat at https://gitter.im/urho3d/Urho3D](https://badges.gitter.im/urho3d/Urho3D.svg)](https://gitter.im/urho3d/Urho3D?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
 **Urho3D** is a free lightweight, cross-platform 2D and 3D game engine implemented in C++ and released under the MIT license. Greatly inspired by OGRE and Horde3D.
 
@@ -141,9 +141,10 @@ Urho3D uses the following third-party libraries:
 - Recast/Detour (https://github.com/memononen/recastnavigation/)
 - SDL 2.0.4 (http://www.libsdl.org/)
 - StanHull (http://codesuppository.blogspot.com/2006/03/john-ratcliffs-code-suppository-blog.html)
-- stb_image 2.10 (http://nothings.org/)
-- stb_image_write 1.01 (http://nothings.org/)
-- stb_vorbis 1.07 (http://nothings.org/)
+- stb_image 2.12 (http://nothings.org/)
+- stb_image_write 1.02 (http://nothings.org/)
+- stb_rect_pack 0.08 (http://nothings.org/)
+- stb_vorbis 1.09 (http://nothings.org/)
 - SQLite 3.8.10.2 (https://www.sqlite.org/)
 - tolua++ 1.0.93 (http://www.codenix.com/~tolua)