Merge pull request #210 from hrydgard/readme-update

Add PPSSPP to the "Software using this library" section of README.md
diff --git a/README.md b/README.md
index 908f274..09dd2cc 100644
--- a/README.md
+++ b/README.md
@@ -158,6 +158,7 @@
 - **[vkQuake2](https://github.com/kondrak/vkQuake2)** - vanilla Quake 2 with Vulkan support. License: GNU GPL.
 - **[Vulkan Best Practice for Mobile Developers](https://github.com/ARM-software/vulkan_best_practice_for_mobile_developers)** from ARM. License: MIT.
 - **[RPCS3](https://github.com/RPCS3/rpcs3)** - PlayStation 3 emulator/debugger. License: GNU GPLv2.
+- **[PPSSPP](https://github.com/hrydgard/ppsspp)** - Playstation Portable emulator/debugger. License: GNU GPLv2+.
 
 [Many other projects on GitHub](https://github.com/search?q=AMD_VULKAN_MEMORY_ALLOCATOR_H&type=Code) and some game development studios that use Vulkan in their games.